Zagreb, Croatia
Before it was unified, Zagreb's upper town (Gornji Grad) consisted of two rival districts which took great pleasure in knocking chunks out of each other at every opportunity - not really surprising, as Kaptol was home to the Bishop and all his riches while Gradec was where you'd find the tradesmen and workers who made the city tick. It was very much a "them and us" deal in medieval Zagreb, until the late 18th century when somebody finally decided that it might be...