Castelfiorentino is a comune (municipality) in the Province of Florence in the Italian region Tuscany, located about 30 km southwest of Florence. As of 31 December 2004, it had a population of 17,604 and an area of 66.6 km². The municipality of Castelfiorentino contains the frazioni (subdivisions, mainly villages and hamlets) Dogana, Castelnuovo d'Elsa, and Petrazzi. Castelfiorentino borders the following municipalities: Certaldo, Empoli, Gambassi Terme, Montaione, Montespertoli, San Miniato.