What if you banned cars from a city?
 

Banning is a strong word that must be avoided, but let's say that you
let in essential vehicles to a city a center and you could actually
ride a donkey in NYC. Well, that's something extreme --except for the
mounted police-- but you get my point. Then people could walk and
bike around with no stress whatsoever.

This will actually happen this Sunday in Brussels, for one day. Every
year the city of Brussels bans all non-essential cars for a day
("car-free day").