Città di Castello ; "Castle Town") is a city and comune in the province of Perugia, in the northern part of Umbria. It is situated on a slope of the Apennines, on the flood plain along the upper part of the river Tiber. The city is 56 km (35 mi) north of Perugia and 104 km (65 mi) south of Cesena on the motorway SS 3 bis. It is connected by the SS 73 with Arezzo and the A1 highway, situated 38 km (23 mi) west. The comune of Città di Castello has an exclave named Monte Ruperto within Marche.

A comune is an administrative division of Italy, roughly equivalent to a township or municipality. It is the third-level administrative division of Italy, after regions and provinces. The comune can also have the title of città.