The most dangerous neighborhood in Paris where the police do not enter

The outskirts of Paris are dotted with extremely dangerous neighborhoods (banlieues), where the police only enter in riot gear and with many men and despite everything, urban guerrilla warfare breaks out.
We went to Grigny with many difficulties and expectations but we managed to enter and talk to some young people who live and work there, to get a cross-section of France where certain groups of citizens are confined to very specific areas and where they often avoid go out because they would find themselves in difficulty outside
Let us know in the comments what you think