The parallel between similarities of modern day stadiums and arenas in many major cities, and structures bearing similar size and shape
to one another shared among major population centers in this part of the ancient world, is striking.
But who are we kidding, the Romans also built massive structures where they could watch people kill one another and/or get eaten by lions. The shape of those structures can definitely still be seen in the design of modern football stadiums.
Edit: autocorrect is messing me up