The Mazaro (Italian: [ˈmaddzaro]; sometimes spelt as Màzaro) is a river in Sicily, Italy.
The Mazaro river flows 28 kilometres (17 mi) across south-western Sicily, from its source in Rapicaldo, located within the Salemi city boundaries, to the Mediterranean Sea in Mazara del Vallo.
Castelvetrano (Sicilian: Castiḍḍuvitranu) is a town and comune in the province of Trapani, Sicily, southern Italy. The archeological site of Selinunte is located within the municipal territory.
The municipality borders with Campobello di Mazara, Mazara del Vallo, Menfi, Montevago, Partanna, Salemi and Santa Ninfa.