Castel Gandolfo (Italian pronunciation: [kaˈstɛl ɡanˈdɔlfo], Latin: Castrum Gandulphi, colloquially Castello in the Castelli Romani dialects) is a small Italian town or comune in Lazio that occupies a height overlooking Lake Albano about 15 miles south-east of Rome, on the Alban Hills. It is best known as the summer residence of the Pope. It is an Italian town with the population of 8834. The town was voted one of the most beautiful towns in Italy.

The resort community includes almost the whole coastline of Lake Albano that is surrounded by many summer residences, villas and cottages built during the 17th century. It houses the Stadio Olimpico that staged the rowing events during the Rome Olympics.

There are also several places of archaeological interest, including the Emissario del Lago Albano and the remains of the Villa of Domitian. The area is included in the boundaries of the Parco Regionale dei Castelli Romani (Regional Park of Castelli Romani). There are also many points of artistic interest, such as the Collegiate Church of St. Thomas of Villanova, designed by Gian Lorenzo Bernini.