Hong KOng, Houston and London are the biggest cities with no zoning.
London at least kinda makes sense and they have a functional underground and transit system. The ring of greenbelts is nice too. That said London CBD traffic before the congestion charges was SOOOOO much worse than it is recently. London is proof positive that congestion charges work. Houston is flat hot and nasty in every way. A pox on that city I wouldn’t every go if it was not the energy capital of north America. Even with the a nearly fully self driving Tesla the traffic is mind numbing.