I've been building a backyard railway for the past 2 1/2 years on my farm just south of Sydney, Australia. Phase 1 of the project is about 300 meters long or around 1000 ft long. The size is 16" gauge size. We've had to move a ton of earth to get reasonably level ground. We built a bridge, and Phase 2 will include a tunnel into a cellar door to taste the wine we make on the property. It's been a really fun project to work on!