I'm a delivery driver in the uk. U-turns are easy even on a turbo roundabout irl. In the UK, if you want to u-turn, you simply indicate towards the last exit, but keep to the inside of the roundabout and ignore one lane divider. This would put you in the same lane for the road you entered in and will merge you with the traffic from the first exit who are taking the last exit relative to them. Hope I explained this well enough:)
We (NL) usually have dashed markings on the complex round-abouts, so can easily switch lines. The lines bring you to the pre-chosen exits, but you are not required to follow them strictly. This enables passing cars (especially useful when the circle is large), and you can also make U-turns. When you accidentally miss your exit, simply get around once more. On small-spaced turbos, we often have strict linings, often enforces with bumps to discomfort switching lanes.
one configuration we (NL) have of the turbo is the 2 lane entry with the priority/main road having the right lane going right and straight instead of right only and the left lane going straight and left. and I love it. it works incredibly well with high traffic roads that pass by towns. it would be the configuration of my choice for a lot of town/city main roads/streets in the US that are currently already 2 lanes wide.
Ended up making the turbo roundabout on my own accord when traffic got so bad I had to force cars to stay in lane. Didn't know it was a thing and had that name till a year later. Intersection marking tool made them very easy to read in-game.
I like this pinwheel roundabout a lot better than the other one. You are looking at the traffic you are about to yield to as you approach. Combined with the curve on entrance to slow you down and make it feel intuitively like you should yield.
Just in fyi, if your roundabout road has a name, you can also click that and then the setup roundabout button on the context menu if you're using the latest version of TM:PE!
i consider a traffic circle the roundabouts where its just a pylon in the center, very easy to convert 4 way stops to these traffic circles with very little expansion of the pavement. Only for very low density residential though, anything more and it would be dangerous.
@@majorphysics3669 That sounds a lot like what we would call a mini-roundabout in the UK, except instead of having any sort of pylon in the centre there would just be a circle painted in the centre that drivers go around. They mainly appear in low traffic areas, but can pop up in busy areas that have limited space.
A traffic circle is an abomination. Imagine a round about, only the traffic already on the circular bit must yield to incoming traffic rather than the other way around. If you only control Entry to the round about with traffic lights instead of yield signs, that's just a roundabout that you've decided needs extra controls for some reason (maybe to facilitate pedestrian crossings, maybe at certain times of day traffic gets bad enough that the round about can't keep up so you need the lights to prevent it locking up?). If the traffic lights can and do also stop traffic that's already IN the circle... yes, that's a traffic circle, which ruins both traffic flow and safety.
@@beeurd there are places in the US with both with and without the pillar and it's found that with the pillar experiences fewer accidents, something-something adding an obstruction reminding people it's a roundabout instead of just and intersection keeps them from hitting it too fast
As far as I understand it, traffic circle is a road arrangement that's basically the same as roundabout except that traffic entering don't yield to traffic already in the roundabout. Traffic circle are designed for high speed entry instead of a modern roundabout which forces slower speed within the roundabout. Needless to say, it's a dumb intersection, it's inefficient and are dangerous because of the high speed. But that's how early conception of traffic circle/roundabouts were conceived, before the design of modern roundabout are properly understood. Basically, a roundabout can turn into traffic circle if driver education is bad and/or the traffic engineers don't put yield sign in the entryway. If driver education is really good, then the yield sign should not really have been necessary as drivers should already know the right of way rules for a roundabout. Roundabouts with traffic signals are called signalised roundabouts, and they can have its benefits, but it kinda also disrupts the free flowing nature of roundabout and the traffic lights also increases operating cost of the roundabouts, which are the two main benefits of roundabouts. The roundabouts that are created just with a cone/pillar or painted circle are called mini-roundabouts. They are low traffic roundabout that can be easily added to existing intersection without many design changes. With proper driver education regarding the right of way rules in a roundabout, it works exactly the same as regular roundabouts. There's not really any drawbacks to it, except that it can really only handle low amount traffic. The ease of converting regular intersection to mini roundabout is why it's popular when traffic is low, it just improves safety in an intersection.
1) I was incorrect in my comment on the pin-wheel roundabout last week. Because I drive on the left hand side I saw straight roads entering the roundabout which would be dangerous and encourage speeding. I now realise that I was seeing exits as entrances. Doh! 2) A good explanation of how roundabouts work and all of your examples exist in the uk although the final one has curbs or massive white zones to keep the existing traffic apart. 3) In the uk all roundabouts are turbo roundabouts but there’s no markings. We just know that is how they work. 4) CSL cannot replicate the most common type of uk roundabout. The mini roundabout is used in suburbs and is just a white blob in the middle of a junction. 5) Once again Yumble your videos are clear and concise.
I commented on the last one suggesting the pinwheel might not perform very well - I still have my doubts about the pinwheel in an area with heavy traffic flow but this super turbo roundabout that prohibits U-turns looks very promising!! I haven't been able to play in a while but I look forward to implementing this soon (I'll give the pinwheel a try too) great video as always :)
This is the downside of vanilla game, some roads are just missing to make great roundabouts, I wish they can do a creator pack with needed roads. I really liked this video. 💞
Yeah they should add a bunch of this stuff in a free update, or at least a DLC, or at the very least, it should all be possible in the sequel (I assume there will be a sequel...)
As a European 😉: the second configuration in our country would have a dashed plus solid line as the double right divider so it's only crossable from the inside of the roundabout. PS, with love, amazing content.
People dont know turbines, in real life they are superbly fast, but they cause a lot of accidents as well, when someone dont lane switch or get confused. All of those are symmetric roundabouts, in poland you have a lot of asymetric ones, where you have extra lane for part that follows priority road. I saw a lot of accidents on one roundabout that had 2 lanes going from south. 1 north, 1 east, 2 west. It completly nukes people ability to follow the markings. just a asymetric turbine with 75% of the way with 3 lanes and 2 lanes on the rest.
@@deilusi Yeah, it's unfortunate to have those who can't use this new kind of solutions, practically in Hungary we don't build new advanced roundabouts because of them. There was a pretty good turbine near my house and it has been converted back to normal 2 lane. Sad but necessity: never had a day not sawing somebody jumping the lanes even they had physical concrete half-sphere pins. It's good we still can build'em @ CS! 😉
I'm from Poland as well and last year I moved to Bulgaria and I had to learn driving again because their multilane roundabouts connected with high traffic are so different than ours that made me feel confused all the time. I was used to drive through similar "roundabouts" with such complexity in Wroclaw too, but there were traffic lights on it which make it no longer the roundabout xd
@@colto2312 yeah, it's called a driving licence?? 😄 that's why you go to driving school and drive with a licensed tutor before they let you take the test
The game is basically unplayable without mods. At the very least, traffic manager is considered by most to be an essential mod for the game. Personally, I couldn't imagine running a city without it.
@@arandombard1197 Always baffled me why Americans say 'I could imagine' or 'I could care less' The term is 'I couldn't imagine' or 'I couldn't care less' . 'I could' doesn't make any sense as a sentence unless expressed as 'I could only imagine what it would be like without'
@@arandombard1197Apologies for calling you American. Its interesting it was an autocorrection. Makes me wonder if all the examples i see of it are also those. I do see alot of uses of it around though.
I wish I had pictures of when I was a child. Here at my city we had the weirdest roundabout. It was a classic 2 lane in and out 2 lane wide roundabout with a 5 points access. BUT at one point of the wheel the inner lane could turn hard left into a single line that crossothe roundabout directly to the other side of the wheel. IT was HELL on earth to drive there.
One roundabout design I've been having quite good experience with is a three-lane roundabout connected to two-lane roads. It's a bit hard to explain what it looks like in text, but I will try. Entering the roundabout, the right lane of the two-lane road is connected to the outer lane of the roundabout. This is for right turns only. The left lane connects only to the inner lane of the roundabout. At each node, the inner lane of the roundabout can continue straight ahead, or move to the middle lane. The middle and outer lanes of the roundabout will always exit. The only lane change permitted anywhere in the roundabout is moving from the inner to the middle lane, on the node before a car exits the roundabout. It is possible to do a U-turn, simply by staying in the inner lane for longer. The main advantage of this setup is that cars making a right turn will not interfere with the other lanes at all. In fact, no cars leaving the roundabout at any node will interfere with the cars entering at that node. However, there is a crossing point where cars preparing to exit at the next node will have to cross into the middle lane while entering cars go into the inner lane. However, I'm not sure if this is actually a good design. It works for me, better than the default roundabout setup, but I cannot help but wonder if it is suboptimal. Looking at the video, it feels like a lesser variant of the Super-Turbo Roundabout, but far simpler and easier to set up. If you use the lane tool and just press Ctrl-S at an intersection between an Avenue and a Highway in the vanilla game, you only need to move two lines at every node to complete the setup.
Thanks for this, it sort of inspired me to pop into my game that has 1000 roundabout offramps and mess with them a little. They're not bad but I can already see hitting 25k + will swamp some of them.
1:46 There are no roundabouts that use traffic lights. When a circular intersection has traffic lights, it's called a Traffic Circle and the behaviors and rules of a Traffic Circle are different than a Roundabout, the only similarity is that they are both circular intersections.
This is absolutely not true - it depends on which country you live in. In the UK for example, the spiritual home of the traffic roundabout, with or without lights they are all roundabouts or to give them their proper term "gyratory traffic flow system". Especially since in many cases, the traffic light are part-time, only being used during rush hours.
They’re upgrading a roundabout near me in Newport, RI, BUT, I think they goofed. At one point in the roundabout, they reduce the circle from two lanes to one, meaning all the traffic trying to enter the roundabout is forced to wait, even if you’re just trying to make a right turn..
Great video that did each individual roundabout type justice. You covered each type of roundabout imaginable (except the one-of-a-kind Magic Roundabout). It seems like a poorly set up roundabout can devastate traffic, but one set up properly will show their full potential.
Roundabouts near me (UK) use your super turbo 1st exit on a lot of medium-sized roundabouts but pull it back from the roundabout a few metres with a pavement divider instead of a white line, this also assists with pedestrians trying to cross larger roundabouts.
I often use a slightly different version to your turbo roundabout: traffic on the inner (left) lane is allowed to stay in the left lane, which allows for U-turns to be made. The lane markings show the lanes on the roundabout, so that traffic driving towards the roundabout have an extra visual cue to give way to traffic already on the roundabout.
This is exactly what I have been doing too! Sometimes disallow u-turns on the bigger stuff. And I agree the markings are the wrong way around, the lane that gives way should cross a line, not the one with priority.
Great video. Nice pace, clear explanations… I’m from the UK and so the concept of roundabouts is very familiar to me. Indeed, my city is full of them (IRL and game). But, I was always struggling with how to manage the lane connectors to avoid unnecessary merging, ease the flow but still allow everyone to get to where they want to. From 07:00 is exactly what I’ve been lookng for! Thank you for this!
It looks so simple, the logic behind is also simple once you understand how it works ^^ My idea would be yielding lines on the entrance of the roundabout. And another thing for easy understanding is: amount of exits in a roundabout need to have same amount of lanes to enter (-1 if you don't want to have the sims turn completly). Example: Roundabout with 6 Exits need to have 5 lanes to enter. And 1 more lane to enter if you want that the sims could turn to the street where they enter the roundabout. maybe now I have confused you :) And as always: really like your style of content, kind of relaxing atmosphere but also helpful in the same time.
The normal turbo roundabout can get very congested in the right turning lane, which also makes it harder to do a right turn ironically. You can easily see the congestion when looking at the single right turning lane fanning out into 3 lanes at the end. The right turn bypass does nicely solve the issue though.
I tried to make one myself in game and it was so fun! I did notice that the turbo roundabouts near where I live are all a slight bit different. This game is really great for demonstrating priority roads this way. I went to dig and I actually came across a few things regarding turbo roundabouts. I noticed something that almost everybody does wrong, including both me and you. The first turbo roundabout (TR from now on) isn't actually a real TR but a large partial TR. A real TR has two exit-lanes. Both the outer and the middle lane can get off the ramp. If you were to allow that in your normal TR, you would actually have what's called a rotor roundabout. Breaking it up there increases capacity. If you do the lane math, it doesn't quite make sense to do it that way. You funnel a two-lane road into one lane for the duration of the roundabout. It works for the partial TR because the two lanes feeding into the roundabout are not two lanes of traffic, just sorting lanes from a single lane road. I have a challenge for you: create every named type of turbo roundabout inside the game. That is Egg, Partial, True, Knee, Spiral, Rotor, and there's also stretched-knee and star but those are just 3 legged variations on knee and star. The rotor is the only variation that has 90 degree symmetry. The others are 180 or none. And one last challenge: recreate the turbo roundabout interchange in Talinn, known as the Haabersti traffic junction. I feel so many people see TR's as a panacea, while they have very specific strengths and uses, which explains why they have so much variation. This would be an interesting exploration.
The two lane roundabout setup (atleast in Australia) is quite rare. I call the style you did a tumble roundabout as you tumble to the outside lane to leave, you mainly see them on semi low-Med traffic suburbs but not major roadways (typically). Typically both lanes entering the roundabout can continue straight ahead and you don’t need to change to the outside lane to exit. this preserves the through traffic aspect while making turning easy too. The best way to replicate this in game is to fork the roads into two one way roads just before the roundabout. The one way “on ramp” is then connected to the roundabout in such a way that it and the “exit ramp” of the crossroad now form a junction, creates a good flow and makes the first exit very easy for the traffic
Wow, I recently subscribed, and I've learned so much already! Been struggling with the markings, node controller (mostly, now I see how awesome it is :D), and generally all the mods in the UnifiedUI menu before I watched your videos. I swear I was making a roundabout yesterday and tried to use logic in real life, but I ended up undecided on the final result. I wished there was a video I could watch.. I guess I'm way too excited, but it was the first video I saw this morning, amazing :D! Wish you tons of subscribers, mate, your videos are very thorough and simple at the same time.
Great video! I’ve never done many roundabouts because I’ve never been happy with how they worked. Some very good tips here. I’ve got to start a new game and give roundabouts a chance, now. Thanks!
The pinwheel roundabout reminds me of a miniature version of the Ring Road in Coventry UK.. In reality navigating it is pretty simple because there is a lot of line Crossing it makes it incredibly dangerous and you have to be absolutely on the ball in order to use it in real life…
I don't usually enforce the turbo as u-turning traffic is quite rare. Most of the time roundabouts work fine with the number of lanes being the total number of connecting roads -1 and the standard TMPE setup. Also if you have many exit lanes you can allow two lanes to exit in the most busy directions (after adding an additional lane to the roundabout). It's common in the UK to be able to go straight on from either approach lane if the road continues as a two lane road after the roundabout (this is usually the case on rural dual-carriageways where a minor road intersects).
I’ve just tried the super turbo in the main entry to my city and it’s cleaned up the traffic really well! Took a little working out with the one way highway entry and exit roads. Got there in the end.
In the already roundabout skeptic US you probably reduced the roundabout supporter faction from 10% to 1% by showing the super turbo; I'd feel lost there. Beyond that, great video! Love your calm way.
Here in the UK the 2nd roundabout you showed is not quite right - the left lane entering the roundabout can go left or straight on (UK left hand drive), the right lane can go straight on or right.... So basically both lanes that enter the round about can exit on the opposite side. This helps when the main route would be straight on and the 2 turning would be used the least. But I like the turbo designs.
If you want to /slightly/ improve the traffic flow through the "super turbo roundabout', you can make the right-turn lane split off before the actual roundabout; that way the traffic turning right won't have to yield at the roundabout and can just slip right through. If you do that, you'll want a 2+1 lane road heading into the roundabout, with 1-lane slipways for each of the rhts, which will combine with the roads heading into the roundabout to make 3+2 approach roads.
Any other traffic leaving the roundabout is forced to take the left-hand lane on the exit road, while those right-turn slip roads feed directly into the right-hand lane, so there's no conflict for right-turn traffic.
It feels like the yield entering the pinwheel doesn't allow for good visibility. The functionality of the super turbo roundabout seems ideal. Thanks for the video!
Hi ya Yumbl I'm loving your channel, I've learnt so much from you. I live in the UK where we have thousands of roundabouts, from experience with roundabouts I don't think this roundabout would work because there is way too much traffic conflict when exiting a junction, one lane feeding into two lanes it should be two dedicated lanes on the roundabout feeding into two lanes in the exit. One other point is on roundabouts you can always drive 360 degrees.
Your two lane example, you can use Asymmetrical 2+1 roads instead, since you have only 1 lane leaving the roundabout, not 2, so the extra lane on a normal 4 lane road isn't used. Same applies for your tubo example using a 3+2 or 3+1 asymmetrical roads. Yet you did do it right with the super turbo LOL.
I'm sticking with the pinwheel design. I have 1 in already and I'm going to put in a 'large' one in a future downtown feature. Thinking center circle is 16 units across
In my country (Spain) a roundabout works as a normal priority road (same rules as a straight road) with roads crossing which must to yield. You can leave the roundabout using only the right line but you can continue if you want, like a normal priority road (you can drive on right line all the roundabout with no problems). If you want to join the roundabout, you have to wait until you don't stop the traffic going inside. We use more lines if there is a lot of traffic leaving a roundabout and you want to go to another exit. I think is quite simple and it works very well
Agree! But we also have "turbo roundabouts", and imo those work better than how they worked before being "turbos". At least that's what happens in my hometown Santander. They added a couple of turbos years ago and now I feel more confortable taking those rather than the crazy 3 lane roundabouts... Oh, and we can do U turns with those too! Great video, btw :)
@@shaneintheuk2026 what?? No way!! If you join a motorway, you have to yield to the traffic already on it. But we're really polite and most of the time if we see a car entering, we create space or even move so they can enter without problem. Where did you drive? Maybe people there drive differently
@@javieraracil782 oh! We must have misunderstood the guidelines. We were told cars would just pull out in front of us. In the uk we tend to behave similarly and let people in so I’m not sure why it worried us so much. I suppose it was the shock of the difference.
To allow U turn you could add U turn spot before the roundabout, at least in the version with green belt between directions. That way, you don't have to enter the roundabout to U turn. To be honest, I have never seen turbo roundabout as shown in the RL, it's usually allowed to either change lanes to right or stay at the left lane. But even those are rare, and usually the it's just the right lane if you intend to leave round and left lane if you want to continue on roundabout.
In the Netherlands you can find Turbo-roundabouts, usually not larger than 2 lanes, Turbo-roundabouts are safer than ordinary multilane roundabouts since changin lanes on the Turbo is not done (also there are ridges between the lanes to make people not switch lanes), you have to pick your lane before you enter the roundabout.
If you ever get bored i would love it if you'd put this in your workshop along with the other items you've built lol i havent gotten the line markings down and these roundabouts look great! Haven't been able to find anything like these in the workshop.
@@YUMBL Oh, I didn't expect this response... I guess that might depend on where you live. There are actually a few roundabout-like signalized intersections in the city that I live in most of the time, so maybe I should just go there and use my own observations to understand how they work...
For the two lane roundabout I prefer not to switch from the inner lane to the exit lane, but to exit directly from the inner lane to the second lane of the destination road. That way the right turns stay conflict free.
at 5:09 you said the upcoming roundabout would be conflict free, but there are actually 5 conflict points per entrance on it , 2 merging and 3 crossing :) Also, in my previous comment i said that the turbo roundabout was actually a regular roundabout with concentric spiral marking; this is half right and half wrong, as after looking into it a bit more i learned that for some turbo roundabout variants they are actually the same thing! I apologise for my mistake and I am excited for the next video :)
Much appreciated! “Conflict free” was certainly wrong phrase. I was trying to describe each exit getting its own dedicated lane. You know what I mean ;)
A good turbo roundabout doesn't necessary force an exit but prevent's more then 2 lanes crossing or merging at a single point but spreading the conflict point out and making them simple, and therefor reduce waits and keeping it flowing.
That's great explanation how to solve a lot of issues in people cities, but -I have 2 things to say. This series needs to mention: a) super short roads, they usually make any problem much worse. They stop traffic behind (mostly on busy crossroads), and it's spreading the problem all over the city. If there is some road behind, before stop & go happens. If you have enough asphalt to absorb the traffic, without clogging the next crossroads, it won't become a jam all over the neighborhood. If you have like medium traffic, leave 20-30u between junctions. for high traffic, it's like 50-60u between them. b) downsides of roundabouts: There is one thing people don't understand as well about roundabouts. It's not an omnipotent solution. if you make a roundabout, you lower the number of "lanes" that you have dedicated for your "main" direction. if you have 3 lanes going in 4 directions, there are 6 lanes that you could use, (But only 1 lane usually that can go left at a time) 3 lane roundabout have 3 lanes in total for all directions, so you downgrade the road as a result. In crossroads you have half of the time for horizontal and half for vertical, which means 6 lane road handle 3 lanes of traffic, nicely (with exception to left turns, as mentioned, another topic) so (3 lane) roundabouts are something that handle 2 full lanes in each direction, but 3'rd clogs it completely. Typically, its (number of lanes-1) is what they can handle. Gain is that its omnidirectional, so left turns and U turns don't cause a buildup. If roundabout is not handling it, Usually the best way is to go back to simple crossroads, but with a twist, you need to block left turns, and make them non-colision way (by ramp or tunnel) like they do on highways. If anything clogs your city, its 69% left turns, 15% lane maths, (when you crunch high traffic 6-7 lanes from each direction on 3 lane roundabout, or general 3 busy lanes to 1), 15% something like train stations, on short/main road. If you solve them in non-colision, on high importance roads, (and that's where roundabout with U turn helps as well)
@@YUMBL I've seen some of them, maybe its already somehere I just havent reached YET. I really liked mod video, my point was that, in there, you did not mention any problems roundabout have, I wanted to leave something for people who see only that. (and I took that crooked roundabout for myself as well, along with one of the highway connections I've seen on your video) I don't agree with that roundabouts are bad, they are awesome for low to medium traffic in all directions. I want to say they are overused, and not one-solve-all tool.
Thats my opinion as well. This just happens to be a video about how to set up roundabouts. Not about alternatives. See my “city starts ranked” or “making traffic use all lanes” videos for my feelings about roundabouts. This simply isnt that video.
@@YUMBL I thought it deserved single sentence like that, that's why I mentioned it, something like "they are good for medium traffic, for high traffic check video x" to put full stop on this topic. I say it again, thanks for through explanation on the topic.
From a traffic management prospective, roundabouts have one very simple problem: A big percentage of the traffic going through it doesn't need to be there. Let me explain: In your example, each road coming in basically is a 1 in 3 out problem. Assuming equal distribution, 33% of the traffic goes to each possible exit, and the 1% remaining gets confused and goes back where they came from. The problem is that this means that 33% of the cars were just going straight and didn't need to slow down, turn, change lanes, and so on. Their trip is actually slowed as a result of the round about. The second problem is that 33% of the cars also want to "turn right" (air quotes because in the UK, they would want to turn left, but you get the idea). So they go into the round about only to immediately leave it at the next road. Their trip is slowed by having to queue, enter the round about, turn, and leave it. There is a third and even more significant knock on problem with all of this, which is simply that this means that 66% of the cars in your roundabout simply don't need to be there. Those 66% end up slowing the 33% that would benefit from the roundabout down, while also having their own trips slowed by having to use the roundabout to start with and being in each other's way. Essentially, no matter how efficient you make a roundabout, it will hit a wall at a certain point and rapidly decline in performance, with the traffic version of dithering. When you break it down, the issue of a roundabout is that it basically slows all traffic to make it somewhat easier for 33% of the traffic to turn left. It's somewhat better than a timed traffic light 4 way intersection, but it's really going a very long way just to allow left turns. My suggestion is this: one road under, one road over elevated, and a mechanism to allow left hand turns in the middle. Right hand turns handled by individual point to point ramps. The middle layer could be a roundabout, because you have removed 66% of the traffic from the equation. It could even be a two cycle left turn only 4 way intersection, again even as it's inefficient in normal use, it would still be able to move a much higher rate of cars compared to the standard 4 way intersection, as you would make no provision for right or straight through. The bigger problem in the end here is that you start to border on making an interchange instead of an intersection. In the real world, the lack of space and the NIMBY view of things like this, it's unlikely you could do this every block!
I agree and at least to change the arrow on the lanes in Vanilla (PS4), without it, you can make a perfect roads but the game would do unreal stupid stuff and block everything...
YUMBLtv - thank you for shown this and explaining it. I always enjoy watching your videos because your roads are so clean, your layouts are beautiful and many of your designs are interesting. Also if I may suggest you might want to consider doing a video on the different types of mods that you use especially on some of these road designs since many people are not fully aware of them and I think it should be shared with the community to bring them up to speed with what you use.
I think one time you'd want to avoid the turbo versions is if you've got, say, a collector road with roundabouts for intersections with other collectors and right-in/right-out intersections with local roads. Think a roundabout-ified RCUT-like thing. That sort of arrangement depends on allowing U-turns at the larger intersections to allow cars from the local roads to proceed across or turn left.
In the 2nd 2 lane example you should be in the right most (left most for here in UK) lane for turning right and taking the second (ahead) exit. If the ahead exit is past the 12 o'clock (11 o'clock side in your example) position then you should be in the inside lane. The 12 o'clock rule is what is taught here in UK unless the signs say different.
And remember, if you really need a u-turn you can just add a 4th/5th lane. Try adding one and see how many people actually use it though. One of the main reasons we don't ever see them is because they'd go nearly unused.
You should also yield on a traffic light controlled roundabout, if you're sticking lights on you roundabout you should try and make nodes separate and keep the yield
Also road traffic rules in the uk suggest you take any left exit (equivalent to a right) and the straight from the left hand lane unless otherwise stated, we do have "turbo" roundabouts as well
Great tutorial. From watching Biffa, and I see he commented here as well, the roundabout typically has 1 more lane than the incoming road. Or, it should at least equal the number of incoming lanes. So a 2 into 2 or 2 into 3 but not a 3 into 2. I did notice, and you did not point this out, that your Super Turbo used an asymmetrical 3+2 with 3 lanes coming into the 4 lane roundabout and 2 lanes going out. That actually makes sense to me. Perhaps you can add an extended version of this video showing how you did the markings?
I love the pin wheal RB, I use it with a 3 lane road with a dedicated tram line. I like this as well with the 4 lane centerpiece. It's the slip lane for the right hand turn that is the key to get a good flow.
Your tutorials have helped me a lot and made Cities much more fun for me. I wonder if the developer has a content contributor program like World of Tanks does. I'd nominate you for sure.
This looks like a huge turbo roundabout. IRL a bit dangerous I think but in Cities skylines this'd work amazingly (mainly as cits have real problems changing lanes.)
You’re exactly right. The lane changing is easy. Irl you wouldnt know youre changing lanes as it pushes you out. Its getting across INTO it thats the problem. The width
This is the kind of thing that probably only works in theory, and not in real life. I've never seen people respect the lanes while inside the roundabout. No-one would (correctly) choose the exit before even entering the roundabout. Unless there were obstacles. Then again, we just need to do this in CS because the engine doesn't let cars change lanes in between nodes and every driver is very polite.
Really good and informative video. However, the talk on City Planners discord about it mostly pointed out how unsafe the pinwheel is due to side merging like you would an on/off ramp for a motorway, but with such limited space it would be very dangerous without a seriously low speed limit. So any of the normal, straight-on roundabouts are going to be safer as, even with a yield, you should be slowed or stopped and easily able to look right (or left) for oncoming traffic rather than trying to look over your shoulder and missing something ahead of you... or hoping the driver is aware of their blindspots and mirrors, etc.
@@YUMBL Not sure why you are imitating Yumbl or trying to bring him down with your poor attitude. But you clearly neglected to read anything I mentioned or pay attention to the video and there being neither a pin or description of relevance to what I mentioned, which was only about real-life safety concerns around a pinwheel compared to standard ones.
Yea. The pinned comment and description say that the version in the steam workshop has been reversed. You should have a look at it as it addresses your concerns. Thats why its relevant.
Killing it with the videos man, well done. Also, after watching through your Newmarket series my Skylines addiction is starting to warm back up. Usually i start, build the city up and get frustrated and delete it, repeat. However I've taken on so many things from that series and these tutorial video's and I do have to thank you. One other thing I have to ask is about the theme/LUT you are using here? Is it something you're currently working on and will share in the near future or are you able to share information on it now? Totally understand if it's the latter. I'm currently sorting through maps (haven't found anything yet) and themes for my next build as it's something I want to start, take my time and persist at. But I'm not happy with anything I'm getting, the colours and textures in your last 2 tutorials is something I'd love to use. So I might hold off and hope you share your secret sauce. Thanks 👍
You or the system have the leftmost two lanes going into the circle marked incorrectly, the first should be a combo arrow combining a straight arrow with a left turn arrow (almost looking like a question mark) the center arrow should be a straight arrow. This will help people pick the correct lane ahead of time.
I’ve grown up with regular roundabouts (also called squares for some odd reason) but you definitely taught me a lot about turbo roundabouts, which I don’t know if I’ve encountered. Drivers are always confused when they encounter roundabouts. I think that education is definitely at fault, and drivers should not be able to have a license unless they know how to drive into and around a roundabout.
@@YUMBL could be, we were colonized by the British, so some things were taken in, others were not, then you throw in some French in the mix, and oh gosh you’ve got a mishmash of words that mean different things in different cultures for some extra spice in conversation. Yes, looong sentence, also cultural difference.
@@YUMBL Town squares often _are_ roundabouts too, in that they're frequently bordered by one-way roads. Very common in South American cities... the oldest part of the city being a plaza with a cathedral on one side, town hall on another, etc, and with the road around the plaza often being "una via".
I don't know why but making U-turns on a turbo roundabout feels satisfying. You're not supposed to, if you follow the lanes. But there is no laws against it and no danger.
Another reason on why you would want a Roundabout is to slow down traffic in a city without needing a traffic light. That is more of an IRL thing tough.
I think some people don't even realize those are technically roundabouts. I'm talking about the "bump in the middle of the intersection you have to drive around" variety.
Never seen any of these. And we have roundabouts in most intersection in my home town. The thing I’m a little concerned about is the fact that you have more lanes inside the roundabout, than from incoming lanes. Here we have 2 lanes in the roundabout itself if there are 2 lanes as the largest incoming road. Since you always has to yield for the traffic inside, and their choice of lane inside desides what exit their going to use. We also have a third lane sometimes for just going right, but it’s mostly detached from the roundabout itself. And merges with the next road as a highway lane coming in. And of cause we have more lanes in the roundabout if there are more lanes coming in. And for clarification. The right incoming lane is for right turning or straight ahead. The left for left or straight if there are a 2 lane road outgoing. But you do not change lanes inside the roundabout when using the left. Then you also depart in the left lane. Meaning you can have double the traffic going straight.
For the last roundabout, it is 3 lanes in entrance but 2 lanes in exit. I think it will look better or more symmetric if the 3 lanes entrance is 2 lanes at the beginning and only expanding itself to 3 lanes when nearing the roundabout. Then the roads outside will be standard 2-by-2 roads.
It's possible to add a conflict-free U-turn option to the super turbo roundabout. I'm thinking, after you complete the right turn, peel an exit lane off of the rightmost side, pull as sharp of a 180 as you can (3x3?), tunnel under/bridge over the road you are returning to, back to surface level, left turn, then rejoin the original road opposite direction. This could be repeated in all four directions with no conflicts if I'm envisioning it correctly (I don't actually play CS, so I could be wrong). With full lane mathematics, you'd actually have to add a fourth lane (a second right turn lane) to the roundabout entrance, but how many U-turns are you anticipating?
A cheaper way to accomplish this is a variant of what I call the Michigan Left Turn, where left turns at an intersection are forbidden, but instead, a modest distance away from the intersection proper, a specific U turn opportunity is provided on the cross street; to make a left turn, one must make a right turn, cross (presumed multiple lanes) to the center median, then make the U turn. For the super Turbo Michigan U Turn (ghod, that name is getting long), provide a break in the median a short-to-modest distance away from the roundabout, node required to change lanes, set up the U turn specifically from the original leftmost lane to the opposite direction leftmost lane. To see how it works, freeze frame the video at 7:17. You start at the purple dot, turn right, change lanes to reach the center median, make the U turn, take the lane change marked in red at the top of the screen, then the lane change marked in blue on the left, and end up opposite direction on the original road (green dot).
@@YUMBL well that's your design choice and as such is fine. Other people might want the option. I personally regard mass use of u turns as a troubleshooting flag that a connection is missing somewhere, so good to bring the issue to the fore, so it can be id'd and fixed.
That super turbo is not unlike a lot of UK motorway junctions/interchanges, especially where two motorways cross or meet. Ours are usually traffic light controlled (although these are often temporary and it's free-flowing during less busy times of day) and may be elevated so one of the motorways is a through-road beneath the roundabout, or even split-level in a way that allows through traffic along both axes. They also irl usually allow you to change lanes to perform a U-turn, which may be used if there's an accident/RTA on a motorway slip road, where the police will close the slip road and force exiting traffic to go to the next exit, all the way around the roundabout, back down the other side of the motorway and then exit from the opposite side. The roundabout where the M180 meets the M18 is one example of this near where I grew up, it's elevated over the M18 and traffic light controlled, but other than that it works a lot like the super turbo shown here (remember we drive on the left, if you decide to take a look at it...!) They look great in CS with all the intersections marked up and the island in the middle decorated, this was a very satisfying video to watch :D
9:34 you can also do a... I'd guess I'd call it partial?... partial turbo roundabout with 2 lanes - 2 of the exits are optional instead of forced, and two of the nodes dont have a forced lane change
looking at the traffic flow at 5:00, wouldn't it always be possible to 'double' every exit, without risk of right hand interactions from the outside 'turn only' lane. you only enter the circ if you need a more distant exit, and you could leave without concern that your right flank is exposed. that would empty the circ quicker to open entry spots for new vehicles, and still allows for a fairly rapid 180. perhaps the traffic mandate could include the mantra 'keep your speed and keep your space in the roundabout', so drivers are not claiming openings created by a vehicle exiting from the inner circle. this would let a driver trying to enter have a spot to claim. take the foot shaped exclusion at the exit by the toe, and pull it halfway back toward the heel. dashed exit arc to suggest exit driving line. the only time you cross a line is when emergency vehicles are requesting space. also picture a light system that shows a green 'proceed arrow' to an incoming driver while showing caution yellow to the driver already in the inner lane and expecting to continue in the inner lane. trigger the lights spontaneously with 2 weight sensors, one for each path decision, so when a vehicle leaves via the inside exit lane, the incoming driver is prompted. the yellow will keep inside lane drivers from claiming the open space by shifting responsibility to them not to 'take the space'. that space, represented as the bottom of the foot, should be long enough for the 'declared speed' to allow time for the incoming driver to take their spot in the inner lane. the incoming driver must ensure his lane exit is clear before he enters the box, as per usual. as one would expect, the yellow yield can be disregarded if the driver verifies there is no incoming vehicle at the next entrance competing for a spot. perhaps a third weight sensor at the entrance to the inner lane would also help decide if the yellow caution lights, and requests a spot, while any vehicle exiting and creating a spot declares the green to proceed. show red to the incoming driver if the inside lane sensor detects a vehicle and enforce the stop, otherwise the green proceed allows entry into an uncongested inner lane.
by adding a fourth lane to the turbo roundabout and having an 8 lane road coming into the roundabout you could allow for U-turns in it though i think the superturbo roundabout is better
@7:09 (turboroundabout) If you allow the cars to exit the roundabout from 2 lanes you can significantly increase throughput going straight over. Cars in the middle lane can choose to exit, or go on to the next exit. This way you utilise more of your exit roads. Make the blue line also exit to the middle lane.
@@YUMBL This way you can have 2 lanes crossing the roundabout, not only 1, the total throughput increases. I see it in real life over here in a lot of places. Try it :D
Love the tutorial. Some thing to use in my city. Wonder, would traffic lights would be best for high density or yeild signs all the way? Something to experiment with. Amazing vids as always.
IRL roundabouts fail when traffic is high or it’s a-symmetrical. If one route never turns right (left in the us) one entrance never gets to go. In that situation traffic lights are better.
@@shaneintheuk2026 Many junctions do (or at least, did) use part-time signals for that very reason just during rush hours. I've been overseas a long time, do they still have them?
My big thing against roundabouts is they are grossly inefficient. You waste gas, and time to transition to desired direction. I recently watched a video where he incorporated a lefthand bypass turn lane. I would take a step further include a right lane bypass and then connect straight through traffic. Of course this then stops becoming a roundabout, however everything is way more efficient. No conflicts with people turning left or right no wasted motion i.e drive 1/2 or 3/4 of a circle in order to head in desired direction.
On your pinwheel roundabout I dont see any need for the inner most lane of the roundabout. If a driver changed into this lane, they would need to immediately move out of it. My city tried something similar and they actually re-did the roundabout after a year and removed the inner lane as it was cause of LOTS of accidents. Anyway, I love your videos!
Very nice, I've made some of your so called Super Turbo Roundabouts myself, I'm proud to have invented it on my own as well. I like the name too, let's make it official. I'm interested however in seeing it compete against a TMPE traffic light, these are damn impressive on high volume traffic. Also I'm not 100% sure on this, but I believe that vehicles yielding are aware of lane connectors, so the slip lane on the Super Turbo should never yield, meaning it's just as good as a dedicated road.
Technically none of these are official "Turborotonde" according to it's creator Bertus Fortuijn (/watch?v=iMYib3IR43I). - Once you get on your lane in the roundabout, you will automatically exit the roundabout by following your lane (due to the spiral shape). - No changing lanes once on the roundabout is allowed/possible. - No crossing 2 or more lanes to get onto the roundabout. The Turbo Roundabout you made is called a "Turboplein" or Turbo Roundabout Interchange and traffic lights are mandatory in the Netherlands due to crossing 2+ lanes at once. Love your videos on these intersections! Please do more!
Something to keep in mind is that in order for proper yielding in a turbo, you need to turn up the setting to medium atleast I believe in TM:PE. Without this you'll get funny things like what we saw in the cinematic with people on the roundabout giving way to those coming on
I think you could still do U-turns in roundabouts without compromising the roundabout's flow. Just expand the roundabout's lanes by 1, allow the leftmost lane entering the roundabout to pick between the 2 innermost lanes instead of just 1 lane, then set it up as normal, and you should now have a roundabout where every vehicle will be forced to stick to a particular lane, yet would also allow for U-turns.
We have a city in Poland, probably there is more in the world like that but.. they love roundabouts, to the point that you can even go from one roundabout to another and then another one.. also, every one of them is looking great and different :D For example they have a district that they call "mexico" and a roundabout there has some cacti, and stuff like dessert :D
The bus route made lane usage of the turbo roundabout very clear.
Glad it helped :)
@@YUMBL is the irl turbo roundabout also designed to disable a u turn or is it just a design choice for cities skylines
Just the CS version from what I’ve seen
I'm a delivery driver in the uk. U-turns are easy even on a turbo roundabout irl. In the UK, if you want to u-turn, you simply indicate towards the last exit, but keep to the inside of the roundabout and ignore one lane divider. This would put you in the same lane for the road you entered in and will merge you with the traffic from the first exit who are taking the last exit relative to them.
Hope I explained this well enough:)
We (NL) usually have dashed markings on the complex round-abouts, so can easily switch lines. The lines bring you to the pre-chosen exits, but you are not required to follow them strictly. This enables passing cars (especially useful when the circle is large), and you can also make U-turns. When you accidentally miss your exit, simply get around once more. On small-spaced turbos, we often have strict linings, often enforces with bumps to discomfort switching lanes.
one configuration we (NL) have of the turbo is the 2 lane entry with the priority/main road having the right lane going right and straight instead of right only and the left lane going straight and left. and I love it. it works incredibly well with high traffic roads that pass by towns. it would be the configuration of my choice for a lot of town/city main roads/streets in the US that are currently already 2 lanes wide.
NL city planning is so incredible.
Here in Belgium, city planner learn a lot about your vision about city planning.
That's pretty cool
Nl?
The Netherlands.
@@conrrr netherlands
Ended up making the turbo roundabout on my own accord when traffic got so bad I had to force cars to stay in lane. Didn't know it was a thing and had that name till a year later. Intersection marking tool made them very easy to read in-game.
I like this pinwheel roundabout a lot better than the other one. You are looking at the traffic you are about to yield to as you approach. Combined with the curve on entrance to slow you down and make it feel intuitively like you should yield.
Yep. The original one was certainly the “left hand traffic” version
Glad I wasn’t the only one. 😀
Yeah! This one is much better and does make the good things that a roundabout has in the first place :)
Just in fyi, if your roundabout road has a name, you can also click that and then the setup roundabout button on the context menu if you're using the latest version of TM:PE!
Nice :-)
Thanks, hombre :)
You say "roundabout" three times and Biffa appears :D
First thing that popped into my head when I saw this come out was "I wonder if Biffa's seen this yet?" haha
@@HrvojeMikovic It's how you summon him like candyman lmao
Time to up that roundabout game......
I would say, if a "roundabout" has traffic lights, then it's actually a traffic circle.
i consider a traffic circle the roundabouts where its just a pylon in the center, very easy to convert 4 way stops to these traffic circles with very little expansion of the pavement. Only for very low density residential though, anything more and it would be dangerous.
@@majorphysics3669 That sounds a lot like what we would call a mini-roundabout in the UK, except instead of having any sort of pylon in the centre there would just be a circle painted in the centre that drivers go around. They mainly appear in low traffic areas, but can pop up in busy areas that have limited space.
A traffic circle is an abomination. Imagine a round about, only the traffic already on the circular bit must yield to incoming traffic rather than the other way around.
If you only control Entry to the round about with traffic lights instead of yield signs, that's just a roundabout that you've decided needs extra controls for some reason (maybe to facilitate pedestrian crossings, maybe at certain times of day traffic gets bad enough that the round about can't keep up so you need the lights to prevent it locking up?). If the traffic lights can and do also stop traffic that's already IN the circle... yes, that's a traffic circle, which ruins both traffic flow and safety.
@@beeurd there are places in the US with both with and without the pillar and it's found that with the pillar experiences fewer accidents, something-something adding an obstruction reminding people it's a roundabout instead of just and intersection keeps them from hitting it too fast
As far as I understand it, traffic circle is a road arrangement that's basically the same as roundabout except that traffic entering don't yield to traffic already in the roundabout. Traffic circle are designed for high speed entry instead of a modern roundabout which forces slower speed within the roundabout.
Needless to say, it's a dumb intersection, it's inefficient and are dangerous because of the high speed. But that's how early conception of traffic circle/roundabouts were conceived, before the design of modern roundabout are properly understood.
Basically, a roundabout can turn into traffic circle if driver education is bad and/or the traffic engineers don't put yield sign in the entryway. If driver education is really good, then the yield sign should not really have been necessary as drivers should already know the right of way rules for a roundabout.
Roundabouts with traffic signals are called signalised roundabouts, and they can have its benefits, but it kinda also disrupts the free flowing nature of roundabout and the traffic lights also increases operating cost of the roundabouts, which are the two main benefits of roundabouts.
The roundabouts that are created just with a cone/pillar or painted circle are called mini-roundabouts. They are low traffic roundabout that can be easily added to existing intersection without many design changes. With proper driver education regarding the right of way rules in a roundabout, it works exactly the same as regular roundabouts. There's not really any drawbacks to it, except that it can really only handle low amount traffic. The ease of converting regular intersection to mini roundabout is why it's popular when traffic is low, it just improves safety in an intersection.
1) I was incorrect in my comment on the pin-wheel roundabout last week. Because I drive on the left hand side I saw straight roads entering the roundabout which would be dangerous and encourage speeding. I now realise that I was seeing exits as entrances. Doh!
2) A good explanation of how roundabouts work and all of your examples exist in the uk although the final one has curbs or massive white zones to keep the existing traffic apart.
3) In the uk all roundabouts are turbo roundabouts but there’s no markings. We just know that is how they work.
4) CSL cannot replicate the most common type of uk roundabout. The mini roundabout is used in suburbs and is just a white blob in the middle of a junction.
5) Once again Yumble your videos are clear and concise.
Excellent! Thank you for watching :)
I commented on the last one suggesting the pinwheel might not perform very well - I still have my doubts about the pinwheel in an area with heavy traffic flow but this super turbo roundabout that prohibits U-turns looks very promising!! I haven't been able to play in a while but I look forward to implementing this soon (I'll give the pinwheel a try too) great video as always :)
Much appreciated! :)
I don't know in real life, but in CS I built a pinwheel for a industrial zone with very high traffic and it works perfectly!
@@nico_7754 nice!!! ill definitely give it a try then
This is the downside of vanilla game, some roads are just missing to make great roundabouts, I wish they can do a creator pack with needed roads.
I really liked this video. 💞
Yeah they should add a bunch of this stuff in a free update, or at least a DLC, or at the very least, it should all be possible in the sequel (I assume there will be a sequel...)
@@PiousMoltaryou foreshadowed life
As a European 😉: the second configuration in our country would have a dashed plus solid line as the double right divider so it's only crossable from the inside of the roundabout.
PS, with love, amazing content.
People dont know turbines, in real life they are superbly fast, but they cause a lot of accidents as well, when someone dont lane switch or get confused.
All of those are symmetric roundabouts, in poland you have a lot of asymetric ones, where you have extra lane for part that follows priority road. I saw a lot of accidents on one roundabout that had 2 lanes going from south. 1 north, 1 east, 2 west. It completly nukes people ability to follow the markings.
just a asymetric turbine with 75% of the way with 3 lanes and 2 lanes on the rest.
@@deilusi Yeah, it's unfortunate to have those who can't use this new kind of solutions, practically in Hungary we don't build new advanced roundabouts because of them. There was a pretty good turbine near my house and it has been converted back to normal 2 lane. Sad but necessity: never had a day not sawing somebody jumping the lanes even they had physical concrete half-sphere pins. It's good we still can build'em @ CS! 😉
I'm from Poland as well and last year I moved to Bulgaria and I had to learn driving again because their multilane roundabouts connected with high traffic are so different than ours that made me feel confused all the time.
I was used to drive through similar "roundabouts" with such complexity in Wroclaw too, but there were traffic lights on it which make it no longer the roundabout xd
mfw you need a phd in roads to drive in europe
@@colto2312 yeah, it's called a driving licence?? 😄 that's why you go to driving school and drive with a licensed tutor before they let you take the test
I like your demo with the bus route tool. Shows the exact path. Nice.
As a console player, this modded stuff looks like straight up magic
And if we can use signs as stop, why can we change the arrows on the lanes? Would be big different in the game!
The game is basically unplayable without mods. At the very least, traffic manager is considered by most to be an essential mod for the game. Personally, I couldn't imagine running a city without it.
@@arandombard1197 Always baffled me why Americans say 'I could imagine' or 'I could care less' The term is 'I couldn't imagine' or 'I couldn't care less' . 'I could' doesn't make any sense as a sentence unless expressed as 'I could only imagine what it would be like without'
@@tosspot1305 I'm not American and it was a typo because I've become over reliant on autocorrection on my writing software and have become sloppy.
@@arandombard1197Apologies for calling you American. Its interesting it was an autocorrection. Makes me wonder if all the examples i see of it are also those. I do see alot of uses of it around though.
I wish I had pictures of when I was a child. Here at my city we had the weirdest roundabout. It was a classic 2 lane in and out 2 lane wide roundabout with a 5 points access. BUT at one point of the wheel the inner lane could turn hard left into a single line that crossothe roundabout directly to the other side of the wheel.
IT was HELL on earth to drive there.
I've used this exact design throughout my city! What a coincidence
Mostly because I see them all the time IRL...but still
One roundabout design I've been having quite good experience with is a three-lane roundabout connected to two-lane roads. It's a bit hard to explain what it looks like in text, but I will try.
Entering the roundabout, the right lane of the two-lane road is connected to the outer lane of the roundabout. This is for right turns only. The left lane connects only to the inner lane of the roundabout. At each node, the inner lane of the roundabout can continue straight ahead, or move to the middle lane. The middle and outer lanes of the roundabout will always exit. The only lane change permitted anywhere in the roundabout is moving from the inner to the middle lane, on the node before a car exits the roundabout. It is possible to do a U-turn, simply by staying in the inner lane for longer.
The main advantage of this setup is that cars making a right turn will not interfere with the other lanes at all. In fact, no cars leaving the roundabout at any node will interfere with the cars entering at that node. However, there is a crossing point where cars preparing to exit at the next node will have to cross into the middle lane while entering cars go into the inner lane.
However, I'm not sure if this is actually a good design. It works for me, better than the default roundabout setup, but I cannot help but wonder if it is suboptimal. Looking at the video, it feels like a lesser variant of the Super-Turbo Roundabout, but far simpler and easier to set up. If you use the lane tool and just press Ctrl-S at an intersection between an Avenue and a Highway in the vanilla game, you only need to move two lines at every node to complete the setup.
Thanks for this, it sort of inspired me to pop into my game that has 1000 roundabout offramps and mess with them a little. They're not bad but I can already see hitting 25k + will swamp some of them.
Thanks for watching :)
1:46 There are no roundabouts that use traffic lights. When a circular intersection has traffic lights, it's called a Traffic Circle and the behaviors and rules of a Traffic Circle are different than a Roundabout, the only similarity is that they are both circular intersections.
This is absolutely not true - it depends on which country you live in. In the UK for example, the spiritual home of the traffic roundabout, with or without lights they are all roundabouts or to give them their proper term "gyratory traffic flow system". Especially since in many cases, the traffic light are part-time, only being used during rush hours.
They’re upgrading a roundabout near me in Newport, RI, BUT, I think they goofed. At one point in the roundabout, they reduce the circle from two lanes to one, meaning all the traffic trying to enter the roundabout is forced to wait, even if you’re just trying to make a right turn..
Great video that did each individual roundabout type justice. You covered each type of roundabout imaginable (except the one-of-a-kind Magic Roundabout). It seems like a poorly set up roundabout can devastate traffic, but one set up properly will show their full potential.
Roundabouts near me (UK) use your super turbo 1st exit on a lot of medium-sized roundabouts but pull it back from the roundabout a few metres with a pavement divider instead of a white line, this also assists with pedestrians trying to cross larger roundabouts.
I've been building turbo roundabouts the whole time without even knowing it :D And it's been fun to watch
I often use a slightly different version to your turbo roundabout: traffic on the inner (left) lane is allowed to stay in the left lane, which allows for U-turns to be made. The lane markings show the lanes on the roundabout, so that traffic driving towards the roundabout have an extra visual cue to give way to traffic already on the roundabout.
This is exactly what I have been doing too! Sometimes disallow u-turns on the bigger stuff. And I agree the markings are the wrong way around, the lane that gives way should cross a line, not the one with priority.
Great video. Nice pace, clear explanations…
I’m from the UK and so the concept of roundabouts is very familiar to me. Indeed, my city is full of them (IRL and game).
But, I was always struggling with how to manage the lane connectors to avoid unnecessary merging, ease the flow but still allow everyone to get to where they want to.
From 07:00 is exactly what I’ve been lookng for! Thank you for this!
Hey, I've been building turbo roundabouts and didn't even know it
It looks so simple, the logic behind is also simple once you understand how it works ^^
My idea would be yielding lines on the entrance of the roundabout.
And another thing for easy understanding is: amount of exits in a roundabout need to have same amount of lanes to enter (-1 if you don't want to have the sims turn completly). Example: Roundabout with 6 Exits need to have 5 lanes to enter. And 1 more lane to enter if you want that the sims could turn to the street where they enter the roundabout.
maybe now I have confused you :)
And as always: really like your style of content, kind of relaxing atmosphere but also helpful in the same time.
I liked adding an extra lane for right turning traffic on the last one :)
Never thought I'd have so much fun learning about roundabouts
Thanks for watching!
The normal turbo roundabout can get very congested in the right turning lane, which also makes it harder to do a right turn ironically. You can easily see the congestion when looking at the single right turning lane fanning out into 3 lanes at the end. The right turn bypass does nicely solve the issue though.
I tried to make one myself in game and it was so fun! I did notice that the turbo roundabouts near where I live are all a slight bit different. This game is really great for demonstrating priority roads this way. I went to dig and I actually came across a few things regarding turbo roundabouts. I noticed something that almost everybody does wrong, including both me and you.
The first turbo roundabout (TR from now on) isn't actually a real TR but a large partial TR. A real TR has two exit-lanes. Both the outer and the middle lane can get off the ramp. If you were to allow that in your normal TR, you would actually have what's called a rotor roundabout. Breaking it up there increases capacity. If you do the lane math, it doesn't quite make sense to do it that way. You funnel a two-lane road into one lane for the duration of the roundabout.
It works for the partial TR because the two lanes feeding into the roundabout are not two lanes of traffic, just sorting lanes from a single lane road.
I have a challenge for you: create every named type of turbo roundabout inside the game. That is Egg, Partial, True, Knee, Spiral, Rotor, and there's also stretched-knee and star but those are just 3 legged variations on knee and star. The rotor is the only variation that has 90 degree symmetry. The others are 180 or none.
And one last challenge: recreate the turbo roundabout interchange in Talinn, known as the Haabersti traffic junction.
I feel so many people see TR's as a panacea, while they have very specific strengths and uses, which explains why they have so much variation. This would be an interesting exploration.
You are totally right! I hope to make a video analyzing a real turbo roundabout soon :)
The two lane roundabout setup (atleast in Australia) is quite rare. I call the style you did a tumble roundabout as you tumble to the outside lane to leave, you mainly see them on semi low-Med traffic suburbs but not major roadways (typically).
Typically both lanes entering the roundabout can continue straight ahead and you don’t need to change to the outside lane to exit. this preserves the through traffic aspect while making turning easy too. The best way to replicate this in game is to fork the roads into two one way roads just before the roundabout. The one way “on ramp” is then connected to the roundabout in such a way that it and the “exit ramp” of the crossroad now form a junction, creates a good flow and makes the first exit very easy for the traffic
Wow, I recently subscribed, and I've learned so much already! Been struggling with the markings, node controller (mostly, now I see how awesome it is :D), and generally all the mods in the UnifiedUI menu before I watched your videos. I swear I was making a roundabout yesterday and tried to use logic in real life, but I ended up undecided on the final result. I wished there was a video I could watch.. I guess I'm way too excited, but it was the first video I saw this morning, amazing :D! Wish you tons of subscribers, mate, your videos are very thorough and simple at the same time.
Glad to help! Much appreciated :)
Great video! I’ve never done many roundabouts because I’ve never been happy with how they worked. Some very good tips here. I’ve got to start a new game and give roundabouts a chance, now. Thanks!
Theyre great! Better than a four way stop. Even when theyre small
The pinwheel roundabout reminds me of a miniature version of the Ring Road in Coventry UK..
In reality navigating it is pretty simple because there is a lot of line Crossing it makes it incredibly dangerous and you have to be absolutely on the ball in order to use it in real life…
that super turbo roundabout is honestly a work of art.
Looking at pics of the lanes exiting makes me smile. :)
I don't usually enforce the turbo as u-turning traffic is quite rare. Most of the time roundabouts work fine with the number of lanes being the total number of connecting roads -1 and the standard TMPE setup.
Also if you have many exit lanes you can allow two lanes to exit in the most busy directions (after adding an additional lane to the roundabout). It's common in the UK to be able to go straight on from either approach lane if the road continues as a two lane road after the roundabout (this is usually the case on rural dual-carriageways where a minor road intersects).
Yep. See the last examples.
I love the super turbo roundabout! This might be just the thing my growing city needs
I was just thinking the same thing. I have a 4-way stop I want to upgrade and this might be the perfect solution.
I’ve just tried the super turbo in the main entry to my city and it’s cleaned up the traffic really well! Took a little working out with the one way highway entry and exit roads. Got there in the end.
I’m glad to hear it! It should hold up, just be sure to add more entrances if necessary :)
In the already roundabout skeptic US you probably reduced the roundabout supporter faction from 10% to 1% by showing the super turbo; I'd feel lost there.
Beyond that, great video! Love your calm way.
Thanks a lot!
Here in the UK the 2nd roundabout you showed is not quite right - the left lane entering the roundabout can go left or straight on (UK left hand drive), the right lane can go straight on or right.... So basically both lanes that enter the round about can exit on the opposite side. This helps when the main route would be straight on and the 2 turning would be used the least. But I like the turbo designs.
If you want to /slightly/ improve the traffic flow through the "super turbo roundabout', you can make the right-turn lane split off before the actual roundabout; that way the traffic turning right won't have to yield at the roundabout and can just slip right through. If you do that, you'll want a 2+1 lane road heading into the roundabout, with 1-lane slipways for each of the rhts, which will combine with the roads heading into the roundabout to make 3+2 approach roads.
They dont actually yield currently. They just come in :)
Any other traffic leaving the roundabout is forced to take the left-hand lane on the exit road, while those right-turn slip roads feed directly into the right-hand lane, so there's no conflict for right-turn traffic.
What a great insight! Using bus lanes to see what your traffic rules are generating. Thank you.
It feels like the yield entering the pinwheel doesn't allow for good visibility. The functionality of the super turbo roundabout seems ideal. Thanks for the video!
Hi ya Yumbl I'm loving your channel, I've learnt so much from you. I live in the UK where we have thousands of roundabouts, from experience with roundabouts I don't think this roundabout would work because there is way too much traffic conflict when exiting a junction, one lane feeding into two lanes it should be two dedicated lanes on the roundabout feeding into two lanes in the exit. One other point is on roundabouts you can always drive 360 degrees.
Your two lane example, you can use Asymmetrical 2+1 roads instead, since you have only 1 lane leaving the roundabout, not 2, so the extra lane on a normal 4 lane road isn't used. Same applies for your tubo example using a 3+2 or 3+1 asymmetrical roads. Yet you did do it right with the super turbo LOL.
A three in one out road is a bit strange. Idk if i have one
@@YUMBL I dunno if a mod has one but at least a 3+2 would work.
I'm sticking with the pinwheel design. I have 1 in already and I'm going to put in a 'large' one in a future downtown feature. Thinking center circle is 16 units across
Nice!
In my country (Spain) a roundabout works as a normal priority road (same rules as a straight road) with roads crossing which must to yield.
You can leave the roundabout using only the right line but you can continue if you want, like a normal priority road (you can drive on right line all the roundabout with no problems). If you want to join the roundabout, you have to wait until you don't stop the traffic going inside. We use more lines if there is a lot of traffic leaving a roundabout and you want to go to another exit. I think is quite simple and it works very well
Well. In Spain we are also famous for the roundabouts with traffic lights, what has not much sense
Agree! But we also have "turbo roundabouts", and imo those work better than how they worked before being "turbos". At least that's what happens in my hometown Santander. They added a couple of turbos years ago and now I feel more confortable taking those rather than the crazy 3 lane roundabouts... Oh, and we can do U turns with those too! Great video, btw :)
As a Brit who drove in Spain on holiday I was terrified that traffic entering a motorway had priority. I was paranoid that I would forget. 😆
@@shaneintheuk2026 what?? No way!! If you join a motorway, you have to yield to the traffic already on it. But we're really polite and most of the time if we see a car entering, we create space or even move so they can enter without problem. Where did you drive? Maybe people there drive differently
@@javieraracil782 oh! We must have misunderstood the guidelines. We were told cars would just pull out in front of us. In the uk we tend to behave similarly and let people in so I’m not sure why it worried us so much. I suppose it was the shock of the difference.
To allow U turn you could add U turn spot before the roundabout, at least in the version with green belt between directions. That way, you don't have to enter the roundabout to U turn.
To be honest, I have never seen turbo roundabout as shown in the RL, it's usually allowed to either change lanes to right or stay at the left lane. But even those are rare, and usually the it's just the right lane if you intend to leave round and left lane if you want to continue on roundabout.
Excellent idea!
In the Netherlands you can find Turbo-roundabouts, usually not larger than 2 lanes, Turbo-roundabouts are safer than ordinary multilane roundabouts since changin lanes on the Turbo is not done (also there are ridges between the lanes to make people not switch lanes), you have to pick your lane before you enter the roundabout.
If you ever get bored i would love it if you'd put this in your workshop along with the other items you've built lol i havent gotten the line markings down and these roundabouts look great! Haven't been able to find anything like these in the workshop.
I am looking forward for a next video on testing the flow efficiency of magic roundabout! Nice video and thank you.
Great video! Speaking of signalized roundabout, I'd love to see a video where you explain how to set these up most efficiently and prevent backups.
I’ve never seen one 😅
@@YUMBL Oh, I didn't expect this response... I guess that might depend on where you live. There are actually a few roundabout-like signalized intersections in the city that I live in most of the time, so maybe I should just go there and use my own observations to understand how they work...
For the two lane roundabout I prefer not to switch from the inner lane to the exit lane, but to exit directly from the inner lane to the second lane of the destination road. That way the right turns stay conflict free.
at 5:09 you said the upcoming roundabout would be conflict free, but there are actually 5 conflict points per entrance on it , 2 merging and 3 crossing :)
Also, in my previous comment i said that the turbo roundabout was actually a regular roundabout with concentric spiral marking; this is half right and half wrong, as after looking into it a bit more i learned that for some turbo roundabout variants they are actually the same thing! I apologise for my mistake and I am excited for the next video :)
Much appreciated! “Conflict free” was certainly wrong phrase. I was trying to describe each exit getting its own dedicated lane. You know what I mean ;)
A good turbo roundabout doesn't necessary force an exit but prevent's more then 2 lanes crossing or merging at a single point but spreading the conflict point out and making them simple, and therefor reduce waits and keeping it flowing.
That's great explanation how to solve a lot of issues in people cities, but -I have 2 things to say. This series needs to mention:
a) super short roads, they usually make any problem much worse. They stop traffic behind (mostly on busy crossroads), and it's spreading the problem all over the city. If there is some road behind, before stop & go happens. If you have enough asphalt to absorb the traffic, without clogging the next crossroads, it won't become a jam all over the neighborhood.
If you have like medium traffic, leave 20-30u between junctions.
for high traffic, it's like 50-60u between them.
b) downsides of roundabouts:
There is one thing people don't understand as well about roundabouts. It's not an omnipotent solution.
if you make a roundabout, you lower the number of "lanes" that you have dedicated for your "main" direction.
if you have 3 lanes going in 4 directions, there are 6 lanes that you could use, (But only 1 lane usually that can go left at a time)
3 lane roundabout have 3 lanes in total for all directions, so you downgrade the road as a result. In crossroads you have half of the time for horizontal and half for vertical, which means 6 lane road handle 3 lanes of traffic, nicely (with exception to left turns, as mentioned, another topic)
so (3 lane) roundabouts are something that handle 2 full lanes in each direction, but 3'rd clogs it completely. Typically, its (number of lanes-1) is what they can handle. Gain is that its omnidirectional, so left turns and U turns don't cause a buildup.
If roundabout is not handling it, Usually the best way is to go back to simple crossroads, but with a twist, you need to block left turns, and make them non-colision way (by ramp or tunnel)
like they do on highways.
If anything clogs your city, its 69% left turns, 15% lane maths, (when you crunch high traffic 6-7 lanes from each direction on 3 lane roundabout, or general 3 busy lanes to 1), 15% something like train stations, on short/main road. If you solve them in non-colision, on high importance roads, (and that's where roundabout with U turn helps as well)
I generally speak quite negatively of roundabouts. I suppose you’ve not seen my other videos?
@@YUMBL I've seen some of them, maybe its already somehere I just havent reached YET. I really liked mod video, my point was that, in there, you did not mention any problems roundabout have, I wanted to leave something for people who see only that. (and I took that crooked roundabout for myself as well, along with one of the highway connections I've seen on your video)
I don't agree with that roundabouts are bad, they are awesome for low to medium traffic in all directions. I want to say they are overused, and not one-solve-all tool.
Thats my opinion as well. This just happens to be a video about how to set up roundabouts. Not about alternatives. See my “city starts ranked” or “making traffic use all lanes” videos for my feelings about roundabouts. This simply isnt that video.
@@YUMBL I thought it deserved single sentence like that, that's why I mentioned it, something like "they are good for medium traffic, for high traffic check video x" to put full stop on this topic. I say it again, thanks for through explanation on the topic.
From a traffic management prospective, roundabouts have one very simple problem: A big percentage of the traffic going through it doesn't need to be there. Let me explain:
In your example, each road coming in basically is a 1 in 3 out problem. Assuming equal distribution, 33% of the traffic goes to each possible exit, and the 1% remaining gets confused and goes back where they came from. The problem is that this means that 33% of the cars were just going straight and didn't need to slow down, turn, change lanes, and so on. Their trip is actually slowed as a result of the round about.
The second problem is that 33% of the cars also want to "turn right" (air quotes because in the UK, they would want to turn left, but you get the idea). So they go into the round about only to immediately leave it at the next road. Their trip is slowed by having to queue, enter the round about, turn, and leave it.
There is a third and even more significant knock on problem with all of this, which is simply that this means that 66% of the cars in your roundabout simply don't need to be there. Those 66% end up slowing the 33% that would benefit from the roundabout down, while also having their own trips slowed by having to use the roundabout to start with and being in each other's way.
Essentially, no matter how efficient you make a roundabout, it will hit a wall at a certain point and rapidly decline in performance, with the traffic version of dithering.
When you break it down, the issue of a roundabout is that it basically slows all traffic to make it somewhat easier for 33% of the traffic to turn left. It's somewhat better than a timed traffic light 4 way intersection, but it's really going a very long way just to allow left turns.
My suggestion is this: one road under, one road over elevated, and a mechanism to allow left hand turns in the middle. Right hand turns handled by individual point to point ramps. The middle layer could be a roundabout, because you have removed 66% of the traffic from the equation. It could even be a two cycle left turn only 4 way intersection, again even as it's inefficient in normal use, it would still be able to move a much higher rate of cars compared to the standard 4 way intersection, as you would make no provision for right or straight through.
The bigger problem in the end here is that you start to border on making an interchange instead of an intersection. In the real world, the lack of space and the NIMBY view of things like this, it's unlikely you could do this every block!
I've actually utilized the pinwheel roundabout as the center piece of my town. It works wonders. I've yet to test it with heavier traffic though.
I agree and at least to change the arrow on the lanes in Vanilla (PS4), without it, you can make a perfect roads but the game would do unreal stupid stuff and block everything...
YUMBLtv - thank you for shown this and explaining it. I always enjoy watching your videos because your roads are so clean, your layouts are beautiful and many of your designs are interesting.
Also if I may suggest you might want to consider doing a video on the different types of mods that you use especially on some of these road designs since many people are not fully aware of them and I think it should be shared with the community to bring them up to speed with what you use.
Thank you! I have lots of videos about mods :)
I think one time you'd want to avoid the turbo versions is if you've got, say, a collector road with roundabouts for intersections with other collectors and right-in/right-out intersections with local roads. Think a roundabout-ified RCUT-like thing. That sort of arrangement depends on allowing U-turns at the larger intersections to allow cars from the local roads to proceed across or turn left.
Okay. This video got me way more excited then it should have. :D
In the 2nd 2 lane example you should be in the right most (left most for here in UK) lane for turning right and taking the second (ahead) exit. If the ahead exit is past the 12 o'clock (11 o'clock side in your example) position then you should be in the inside lane. The 12 o'clock rule is what is taught here in UK unless the signs say different.
And remember, if you really need a u-turn you can just add a 4th/5th lane. Try adding one and see how many people actually use it though. One of the main reasons we don't ever see them is because they'd go nearly unused.
I had to address it. Theres always someone who says “why can’t I turn around in it?” Because you’re a hazard.
You can also add another lane for U-turns if it becomes a problem
You should also yield on a traffic light controlled roundabout, if you're sticking lights on you roundabout you should try and make nodes separate and keep the yield
Also road traffic rules in the uk suggest you take any left exit (equivalent to a right) and the straight from the left hand lane unless otherwise stated, we do have "turbo" roundabouts as well
Aah roundabouts, one of my favourite things in Cities Skylines with obviously left side of the road driving 😉
Great tutorial. From watching Biffa, and I see he commented here as well, the roundabout typically has 1 more lane than the incoming road. Or, it should at least equal the number of incoming lanes. So a 2 into 2 or 2 into 3 but not a 3 into 2. I did notice, and you did not point this out, that your Super Turbo used an asymmetrical 3+2 with 3 lanes coming into the 4 lane roundabout and 2 lanes going out. That actually makes sense to me. Perhaps you can add an extended version of this video showing how you did the markings?
I do intend to make another intersection marking tool vid in the future. Thanks for watching :)
I love the pin wheal RB, I use it with a 3 lane road with a dedicated tram line. I like this as well with the 4 lane centerpiece. It's the slip lane for the right hand turn that is the key to get a good flow.
Getting right turning traffic out is usually an easy victory. Slips are key! :)
Proper roundabouts always eludes me now I shall go forth and apply these techniques 🙂
Have fun!
Your tutorials have helped me a lot and made Cities much more fun for me. I wonder if the developer has a content contributor program like World of Tanks does. I'd nominate you for sure.
Glad to hear it! I’m not sure they know who I am 😂
@@YUMBL if they're paying attention to the community they do. :)
This looks like a huge turbo roundabout. IRL a bit dangerous I think but in Cities skylines this'd work amazingly (mainly as cits have real problems changing lanes.)
You’re exactly right. The lane changing is easy. Irl you wouldnt know youre changing lanes as it pushes you out. Its getting across INTO it thats the problem. The width
This is the kind of thing that probably only works in theory, and not in real life. I've never seen people respect the lanes while inside the roundabout. No-one would (correctly) choose the exit before even entering the roundabout. Unless there were obstacles.
Then again, we just need to do this in CS because the engine doesn't let cars change lanes in between nodes and every driver is very polite.
Some turbo roundabouts have little curbs. You would certainly notice if you didnt keep to your lane
Really good and informative video.
However, the talk on City Planners discord about it mostly pointed out how unsafe the pinwheel is due to side merging like you would an on/off ramp for a motorway, but with such limited space it would be very dangerous without a seriously low speed limit. So any of the normal, straight-on roundabouts are going to be safer as, even with a yield, you should be slowed or stopped and easily able to look right (or left) for oncoming traffic rather than trying to look over your shoulder and missing something ahead of you... or hoping the driver is aware of their blindspots and mirrors, etc.
You neglected to read the pinned comment. Or the description. The design has been reversed for the steam workshop version.
@@YUMBL Not sure why you are imitating Yumbl or trying to bring him down with your poor attitude. But you clearly neglected to read anything I mentioned or pay attention to the video and there being neither a pin or description of relevance to what I mentioned, which was only about real-life safety concerns around a pinwheel compared to standard ones.
Yea. The pinned comment and description say that the version in the steam workshop has been reversed. You should have a look at it as it addresses your concerns. Thats why its relevant.
I’m sorry but you made the same comment as about 200 other people. I’m well aware.
Great looking roundabouts! I'm glad I've stumbled upon this channel.
Welcome in! :)
Killing it with the videos man, well done.
Also, after watching through your Newmarket series my Skylines addiction is starting to warm back up. Usually i start, build the city up and get frustrated and delete it, repeat.
However I've taken on so many things from that series and these tutorial video's and I do have to thank you.
One other thing I have to ask is about the theme/LUT you are using here? Is it something you're currently working on and will share in the near future or are you able to share information on it now? Totally understand if it's the latter.
I'm currently sorting through maps (haven't found anything yet) and themes for my next build as it's something I want to start, take my time and persist at. But I'm not happy with anything I'm getting, the colours and textures in your last 2 tutorials is something I'd love to use. So I might hold off and hope you share your secret sauce.
Thanks 👍
Thanks a lot! The theme is “nature reserve temperate”
Thanks mate
You or the system have the leftmost two lanes going into the circle marked incorrectly, the first should be a combo arrow combining a straight arrow with a left turn arrow (almost looking like a question mark) the center arrow should be a straight arrow. This will help people pick the correct lane ahead of time.
I’ve grown up with regular roundabouts (also called squares for some odd reason) but you definitely taught me a lot about turbo roundabouts, which I don’t know if I’ve encountered. Drivers are always confused when they encounter roundabouts. I think that education is definitely at fault, and drivers should not be able to have a license unless they know how to drive into and around a roundabout.
I wonder if “square” means town square. Like a bunch of space with no buildings. Just a hunch
@@YUMBL could be, we were colonized by the British, so some things were taken in, others were not, then you throw in some French in the mix, and oh gosh you’ve got a mishmash of words that mean different things in different cultures for some extra spice in conversation. Yes, looong sentence, also cultural difference.
@@YUMBL Town squares often _are_ roundabouts too, in that they're frequently bordered by one-way roads. Very common in South American cities... the oldest part of the city being a plaza with a cathedral on one side, town hall on another, etc, and with the road around the plaza often being "una via".
I don't know why but making U-turns on a turbo roundabout feels satisfying. You're not supposed to, if you follow the lanes. But there is no laws against it and no danger.
How about going all the way around once THEN taking your usual exit 😂
If the queue in right lane is long and you need to go right on the roundabout sometimes it's a good trick to go in the left lane and circle around.
Great info on the round-a-bout!
Another reason on why you would want a Roundabout is to slow down traffic in a city without needing a traffic light. That is more of an IRL thing tough.
I think some people don't even realize those are technically roundabouts. I'm talking about the "bump in the middle of the intersection you have to drive around" variety.
Must say, sheer brilliance and just looks the part.
Much appreciated :)
You're pretty close to reinventing a Swindon Magic Roundabout ;)
Never seen any of these. And we have roundabouts in most intersection in my home town. The thing I’m a little concerned about is the fact that you have more lanes inside the roundabout, than from incoming lanes. Here we have 2 lanes in the roundabout itself if there are 2 lanes as the largest incoming road. Since you always has to yield for the traffic inside, and their choice of lane inside desides what exit their going to use. We also have a third lane sometimes for just going right, but it’s mostly detached from the roundabout itself. And merges with the next road as a highway lane coming in. And of cause we have more lanes in the roundabout if there are more lanes coming in.
And for clarification. The right incoming lane is for right turning or straight ahead. The left for left or straight if there are a 2 lane road outgoing. But you do not change lanes inside the roundabout when using the left. Then you also depart in the left lane. Meaning you can have double the traffic going straight.
For the last roundabout, it is 3 lanes in entrance but 2 lanes in exit. I think it will look better or more symmetric if the 3 lanes entrance is 2 lanes at the beginning and only expanding itself to 3 lanes when nearing the roundabout. Then the roads outside will be standard 2-by-2 roads.
Agreed! Thats how I would do it in a build.
Very nice vid!! Only critique I have is the lack of sharkteeth indicating the yield situation. Keep it up!! Greetz, MaxFX
Thanks Max!
It's possible to add a conflict-free U-turn option to the super turbo roundabout. I'm thinking, after you complete the right turn, peel an exit lane off of the rightmost side, pull as sharp of a 180 as you can (3x3?), tunnel under/bridge over the road you are returning to, back to surface level, left turn, then rejoin the original road opposite direction. This could be repeated in all four directions with no conflicts if I'm envisioning it correctly (I don't actually play CS, so I could be wrong). With full lane mathematics, you'd actually have to add a fourth lane (a second right turn lane) to the roundabout entrance, but how many U-turns are you anticipating?
I dont generally accommodate for uturns ever. Traffic must find a way ;)
A cheaper way to accomplish this is a variant of what I call the Michigan Left Turn, where left turns at an intersection are forbidden, but instead, a modest distance away from the intersection proper, a specific U turn opportunity is provided on the cross street; to make a left turn, one must make a right turn, cross (presumed multiple lanes) to the center median, then make the U turn. For the super Turbo Michigan U Turn (ghod, that name is getting long), provide a break in the median a short-to-modest distance away from the roundabout, node required to change lanes, set up the U turn specifically from the original leftmost lane to the opposite direction leftmost lane. To see how it works, freeze frame the video at 7:17. You start at the purple dot, turn right, change lanes to reach the center median, make the U turn, take the lane change marked in red at the top of the screen, then the lane change marked in blue on the left, and end up opposite direction on the original road (green dot).
@Robert Johnson the above thoughts might interest you
@@YUMBL well that's your design choice and as such is fine. Other people might want the option. I personally regard mass use of u turns as a troubleshooting flag that a connection is missing somewhere, so good to bring the issue to the fore, so it can be id'd and fixed.
That super turbo is not unlike a lot of UK motorway junctions/interchanges, especially where two motorways cross or meet. Ours are usually traffic light controlled (although these are often temporary and it's free-flowing during less busy times of day) and may be elevated so one of the motorways is a through-road beneath the roundabout, or even split-level in a way that allows through traffic along both axes. They also irl usually allow you to change lanes to perform a U-turn, which may be used if there's an accident/RTA on a motorway slip road, where the police will close the slip road and force exiting traffic to go to the next exit, all the way around the roundabout, back down the other side of the motorway and then exit from the opposite side. The roundabout where the M180 meets the M18 is one example of this near where I grew up, it's elevated over the M18 and traffic light controlled, but other than that it works a lot like the super turbo shown here (remember we drive on the left, if you decide to take a look at it...!) They look great in CS with all the intersections marked up and the island in the middle decorated, this was a very satisfying video to watch :D
Thanks a lot! :)
need more vanilla options (variants)! and thanx for your work!
9:34 you can also do a... I'd guess I'd call it partial?... partial turbo roundabout with 2 lanes - 2 of the exits are optional instead of forced, and two of the nodes dont have a forced lane change
looking at the traffic flow at 5:00, wouldn't it always be possible to 'double' every exit, without risk of right hand interactions from the outside 'turn only' lane. you only enter the circ if you need a more distant exit, and you could leave without concern that your right flank is exposed. that would empty the circ quicker to open entry spots for new vehicles, and still allows for a fairly rapid 180. perhaps the traffic mandate could include the mantra 'keep your speed and keep your space in the roundabout', so drivers are not claiming openings created by a vehicle exiting from the inner circle. this would let a driver trying to enter have a spot to claim. take the foot shaped exclusion at the exit by the toe, and pull it halfway back toward the heel. dashed exit arc to suggest exit driving line. the only time you cross a line is when emergency vehicles are requesting space. also picture a light system that shows a green 'proceed arrow' to an incoming driver while showing caution yellow to the driver already in the inner lane and expecting to continue in the inner lane. trigger the lights spontaneously with 2 weight sensors, one for each path decision, so when a vehicle leaves via the inside exit lane, the incoming driver is prompted. the yellow will keep inside lane drivers from claiming the open space by shifting responsibility to them not to 'take the space'. that space, represented as the bottom of the foot, should be long enough for the 'declared speed' to allow time for the incoming driver to take their spot in the inner lane. the incoming driver must ensure his lane exit is clear before he enters the box, as per usual. as one would expect, the yellow yield can be disregarded if the driver verifies there is no incoming vehicle at the next entrance competing for a spot. perhaps a third weight sensor at the entrance to the inner lane would also help decide if the yellow caution lights, and requests a spot, while any vehicle exiting and creating a spot declares the green to proceed. show red to the incoming driver if the inside lane sensor detects a vehicle and enforce the stop, otherwise the green proceed allows entry into an uncongested inner lane.
by adding a fourth lane to the turbo roundabout and having an 8 lane road coming into the roundabout you could allow for U-turns in it though i think the superturbo roundabout is better
@7:09 (turboroundabout) If you allow the cars to exit the roundabout from 2 lanes you can significantly increase throughput going straight over. Cars in the middle lane can choose to exit, or go on to the next exit. This way you utilise more of your exit roads. Make the blue line also exit to the middle lane.
Ive found that exiting is never the problem with roundabouts. Its entering. Cars backing up and being unable to get in. Idk if this will help them
@@YUMBL This way you can have 2 lanes crossing the roundabout, not only 1, the total throughput increases. I see it in real life over here in a lot of places. Try it :D
I did try it. Once its backed up on all sides its still over. Traffic piles up.
you could enable u-turns on those spiral roundabouts by allowing them to stay in the inner lane.
Love the tutorial. Some thing to use in my city. Wonder, would traffic lights would be best for high density or yeild signs all the way? Something to experiment with. Amazing vids as always.
IRL roundabouts fail when traffic is high or it’s a-symmetrical. If one route never turns right (left in the us) one entrance never gets to go. In that situation traffic lights are better.
@@shaneintheuk2026 Many junctions do (or at least, did) use part-time signals for that very reason just during rush hours. I've been overseas a long time, do they still have them?
@@poruatokin yes they do. Most major roundabouts have lights that are active in rush hour but switched off during the quieter times of day.
My big thing against roundabouts is they are grossly inefficient. You waste gas, and time to transition to desired direction. I recently watched a video where he incorporated a lefthand bypass turn lane. I would take a step further include a right lane bypass and then connect straight through traffic. Of course this then stops becoming a roundabout, however everything is way more efficient. No conflicts with people turning left or right no wasted motion i.e drive 1/2 or 3/4 of a circle in order to head in desired direction.
On your pinwheel roundabout I dont see any need for the inner most lane of the roundabout. If a driver changed into this lane, they would need to immediately move out of it. My city tried something similar and they actually re-did the roundabout after a year and removed the inner lane as it was cause of LOTS of accidents.
Anyway, I love your videos!
Thanks a lot!
Very nice, I've made some of your so called Super Turbo Roundabouts myself, I'm proud to have invented it on my own as well. I like the name too, let's make it official. I'm interested however in seeing it compete against a TMPE traffic light, these are damn impressive on high volume traffic.
Also I'm not 100% sure on this, but I believe that vehicles yielding are aware of lane connectors, so the slip lane on the Super Turbo should never yield, meaning it's just as good as a dedicated road.
Technically none of these are official "Turborotonde" according to it's creator Bertus Fortuijn (/watch?v=iMYib3IR43I).
- Once you get on your lane in the roundabout, you will automatically exit the roundabout by following your lane (due to the spiral shape).
- No changing lanes once on the roundabout is allowed/possible.
- No crossing 2 or more lanes to get onto the roundabout.
The Turbo Roundabout you made is called a "Turboplein" or Turbo Roundabout Interchange and traffic lights are mandatory in the Netherlands due to crossing 2+ lanes at once.
Love your videos on these intersections! Please do more!
Much appreciated :)
@@YUMBL Here is a video of both regular turbo roundabouts and the turboplein design from a drivers perspective: watch?v=2F3Xql0irEQ.
Something to keep in mind is that in order for proper yielding in a turbo, you need to turn up the setting to medium atleast I believe in TM:PE. Without this you'll get funny things like what we saw in the cinematic with people on the roundabout giving way to those coming on
Are you sure thats how that setting works?
I think you could still do U-turns in roundabouts without compromising the roundabout's flow. Just expand the roundabout's lanes by 1, allow the leftmost lane entering the roundabout to pick between the 2 innermost lanes instead of just 1 lane, then set it up as normal, and you should now have a roundabout where every vehicle will be forced to stick to a particular lane, yet would also allow for U-turns.
So a 5 lane roundabout then?
@@YUMBL Yes, though only assuming that you'd have 4 lanes entering it, and assuming that there's a slip lane to make a right turn.
I'd like this for a screensaver. Looking at good traffic flow is so relaxing
👍Like your style👍
Much appreciated :)
We have a city in Poland, probably there is more in the world like that but.. they love roundabouts, to the point that you can even go from one roundabout to another and then another one.. also, every one of them is looking great and different :D
For example they have a district that they call "mexico" and a roundabout there has some cacti, and stuff like dessert :D