Città di Castello is found in an ancient Umbrian settlement, on the fertile banks of the Tiber. The town, maintaining a large part of the buildings raised during its period of flourishing, is unusual in that it has two central squares. Equally important throughout its entire history, Piazza Gabriotti and Piazza Matteotti, once called Piazza delle Donne and Piazza Vitelli, were known by the locals as Upper Square and Lower Square. The cathedral, found in Lower Square, has a cylindrical campanile and bears the name of a local bishop, San Florido, who was sanctified and seen as a protector of the town. In the 6th century, San Florido supported the rebuilding of the settlement after the destruction by the Ostrogoths. The City Hall building dates from the 14th century and is the work of Angelo da Orvieto, who built the Palazzo del Podestà in the neighbouring square. The Torre civica is the symbol of communal power.