Augusta, Swabian castle in Augusta, Italy.Clemensfranztown, Sicily, Italy, north of the city of Syracuse; it lies on a long sandy island off the southeast coast between the Golfo (gulf) di Augusta and the Ionian Sea and is connected by two bridges with the mainland. The town was founded near the site of the ancient Dorian town of Megara Hyblaea in 1232 by Emperor Frederick II for the rebellious people of Centuripe and Montalbano, towns that were destroyed because of their disaffection. Frederick called it Augusta Veneranda, and it became one of his favourite resorts. The town was rebuilt after the earthquake of 1693. It was chosen by the Knights of Malta to be a supply repository at the beginning of the 19th century. In 1861 Augusta (also spelled Agosta) became part of the Kingdom of Italy. In World War II it was one of the ports of disembarkation of the Anglo-American forces for the invasion of Sicily on July 10, 1943. Notable landmarks include the Swabian castle (now a prison), the cathedral (1769), and the Palazzo Comunale (1699).

The traditional industries are agriculture (cereals, olives, grapes, market produce), salt mining along the coast, fishing, and the preserving of anchovy. Long a naval station, Augusta has become a principal Sicilian trading port, with industrial growth on its extensive waterfront, including an oil refinery and a large chemical complex, which have caused severe environmental pollution problems. Pop. (2006 est.) mun., 33,939.