Why are Walled Cities Round?

Old walled cities can have many shapes, but for mathematical reasons, circular ones are the best. Find out why. Twitter: @TPointMath Music: Angevin B Kevin MacLeod () Licensed under Creative Commons: By Attribution 3.0 License Images: Avila: Choniron Great wall: Great wall: Jakub Hałun Brick laying: Scott Lewis Metal circle: Brian Snelson Manhole cover: Retinafunk Eye: Corinne Kuhlmann Eclipse: Michail Kirkov Mongols: Andrew