Lisbon (lĭz´bәn), Port. Lisboa, ancient Olisipo, city (1991 pop. 677,790), W Portugal, capital of Portugal and of Lisboa dist., on the Tagus River where it broadens to enter the Atlantic Ocean. Lisbon is Portugal's largest city and its cultural, administrative, commercial, and industrial hub. It has one of the best harbors in Europe, handling a large trade, and it has become a major cruise port. Agricultural and forest products and fish are exported. The city's industries include the production of textiles, chemicals, and steel; oil and sugar refining; and shipbuilding. A large transient and tourist trade is drawn to Lisbon, which is set on seven terraced hills.
The Castelo de São Jorge, a fort that dominates the city, may have been built by the Romans on the site of the citadel of the early inhabitants, who traded with Phoenician and Carthaginian navigators. The Romans occupied the town in 205 b.c. It was conquered by the Moors in 714. The city's true importance dates, however, from 1147, when King Alfonso I, with the help of Crusaders, drove out the Moors. Alfonso III transferred (c.1260) his court there from Coimbra, and the city rose to great prosperity in the 16th cent. with the establishment of Portugal's empire in Africa and India.
Although many of the old buildings were destroyed by earthquakes, particularly the disastrous earthquake of 1755, some of the medieval buildings remain. The old quarter, the picturesque and crowded Alfama, surrounds the 12th-century Romanesque cathedral (rebuilt later). The new quarter, built by the marqués de Pombal after the great earthquake, centers about a large square, the Terreiro do Paço. Some well-known buildings in and near Lisbon are the Renaissance Monastery of São Vicente de Fora, with the tombs of the Braganza kings; the Church of St. Roque, with the fine Chapel of St. John (built by John V in the 18th cent.); and the magnificent monastery at Belém, on the north bank of the Tagus facing the sea, built by Manuel I to commemorate the discovery of the route to India by Vasco da Gama.
Among the city's many art museums are the Calouste Gulbenkian Museum, the Modern Art Center, and the Ancient Art Museum; there are also museums devoted to archeology, seafaring, science, coaches, and other fields and specialties. The Univ. of Lisbon (founded 1292, but transferred to Coimbra in 1537), was reestablished in Lisbon in 1911, and the Portuguese poet Camões was born in Lisbon. In 1966 the Ponte 25 de Abril (25th of April Bridge), one of the world's longest (3,323 ft/1,013 m) suspension bridges, was completed across the Tagus. A world's fair was held in the city in 1998, and it left Lisbon with a new aquarium, the Oceanarium, and a large park, the Parque das Nações, as well as the 10-mi (17-km) Vasco da Gama bridge, which crosses the Tagus and has a cable-stayed main span.