a town of Sicily, in the province of Trapani, 24 m. W.S.W. of Palermo direct (51 1/2 m. by rail). Pop. (1881) 37,497; (1901) 51,809. It was founded in A.D. 828 by the Saracenic chief Al-Kamuk, who erected the castle (which still stands, though considerably altered), but was christianized by the emperor Frederick II. in 1233, who removed the site lower down. It possesses some medieval buildings of interest. The surrounding district is very fertile and the trade in agricultural products is considerable.