Explanation: Roman coloniae were built in a very orderly and rational fashion, as planned cities with a grid of streets and the best position possible. Such coloniae were built to imitate Rome as closely as possible - in style, in local government, in the forums and arenas and temples. One might be tempted to think that their glories would pale to Rome itself! But the city of Rome was a few farming villages which, bit by bit, morphed into the largest city in the world at the time. It was infamous, even to Roman writers, as a clogged labyrinth with narrow streets and winding roads; a metropolis of filth shadowed over by hundreds of years of architectural marvels.
Better, I believe, though it also had problems with sprawl from growth. Back when it was Byzantium it got razed to the ground and rebuilt by Emperor Septimius Severus, so they had a clean slate to start from. I'm not real well informed on the topic of Byzantium/Constantinople/Istanbul, though.