city, capital, and principal seaport of Cádiz provincia (province) in the comunidad autónoma (autonomous community) of Andalusia, southwestern Spain. The city is situated on a long, narrow peninsula extending into the Gulf of Cádiz (Cádiz, Gulf of) (an inlet of the Atlantic Ocean). With a 6- to 7-mile (9.5- to 11-km) circumference, hemmed in by the sea from which it is protected by walls, the city has only one land exit.

Traditionally said to be founded as Gadir (meaning “an enclosure”) by Phoenician merchants from Tyre as early as 1100 BC, it was occupied by the Carthaginians about 501 BC. Credence was given to the city's Phoenician origins by discoveries in 1980 and earlier of Phoenician sarcophagi at two separate sites.

At the close of the Second Punic War, the city willingly surrendered to Rome and from that time, as Gades, steadily increased in prosperity. A Roman theatre, one of the oldest and best-preserved in Spain, was discovered in the suburb of Pópulo in 1980. In the 5th century the city was destroyed by the Visigoths. Moorish rule over the port, which was renamed Jazīrat Qādis, lasted from 711 until 1262, when Cádiz was captured and rebuilt by Alfonso X of Castile.

Its renewed prosperity dated from the discovery of America in 1492, when it became the headquarters of the Spanish treasure fleets. During the 16th century it repelled a series of raids by Barbary corsairs; in 1587 its harbour shipping was burned by an English squadron under Sir Francis Drake. After being blockaded (1797–98) and bombarded (1800) by the British, it was besieged by the French in 1810–12, during which time it served as the capital of all of Spain not under the control of Napoleon. There the Cortes (Spanish parliament) met and enacted the famous liberal constitution of March 1812.

The loss of the Spanish colonies in the Americas dealt a blow to the trade of Cádiz from which it never recovered. Its decline was later accelerated by the disasters of the Spanish-American War of 1898 and by its antiquated harbour works. After 1900, considerable improvements were made in quayside construction, and recovery proceeded steadily. In the Spanish Civil War (1936–39) Cádiz fell to the Nationalists almost at once and served as an important port of entry for reinforcements from Spanish Morocco. In 1947 the city suffered great damage from the explosion of a naval arms store.

Industrial development is rather limited, but important naval and mercantile shipbuilding yards and various factories exist on the mainland (metalworking and food processing), and there are tuna fisheries off the coast. The city is primarily a commercial port, exporting wine (principally sherry from Jerez de la Frontera), salt, olives, figs, cork, and salted fish and importing coal, iron and machinery, timber, cereals, coffee, and other foodstuffs. Several shipping lines call there, and passenger traffic is important, mainly to the Canary Islands. A military airfield and a Spanish-U.S. air base, Rota, are nearby. Along the Bay of Cádiz (Cádiz, Bay of), a metropolitan area has formed with a commercial centre.

Notable landmarks include the old cathedral, originally built by Alfonso X of Castile (1252–84) and rebuilt after 1596; and the Baroque cathedral, begun in 1722 and completed in 1838, where the composer Manuel de Falla (1876–1946) is buried and which holds a magnificent collection of art treasures. Other landmarks include San Sebastián and Santa Catalina castles, numerous museums, and the famous Torre de Vigía (100 feet 【30 metres】), a signal tower in the centre of the city. Cádiz's lively annual carnival, held the week leading up to Shrove Tuesday, includes processions, costumes, music, dancing, and contests. The celebration is modeled after the renowned carnivals of Venice, which had an active trade with Cádiz in the 16th century. Pop. (2007 est.) 128,554.

provincia (province) in the comunidad autónoma (autonomous community) of Andalusia, southwestern Spain, fronting the Mediterranean Sea to the southeast and the Atlantic Ocean to the west. It was formed in 1833 from districts taken from Sevilla. The enclave of Ceuta on the Moroccan coast was administratively part of Cádiz until 1995.

The eastern part of the province is crossed by wooded spurs of the Baetic Cordillera, while the west-central part is a low plain crossed by the Guadalete and Barbate rivers and their tributaries. Along the coast are numerous salt ponds that constitute the basis for one of the province's most important industries. The provincial coastline also has important harbours, including the Bays of Gibraltar and Cádiz. Point Tarifa (Point Marroquí), on the Strait of Gibraltar, is the southernmost cape on the European mainland. The mild climate and naturally fertile soil make fruit and vine growing the chief economic activities, though severe droughts often cause great distress. Jerez de la Frontera is famous for the production and export of sherry. Cork is obtained from the mountain forests, and fish are caught off the coast (at Algeciras and Barbate) and salted for export. Much salt is obtained by evaporation of seawater in pans near Cádiz city. The city used to be a shipbuilding centre, but now the manufacturing of parts for the oil and gas industry are prominent near the Bay of Cádiz. The petrochemical industry is dominant in Algeciras Bay. Apart from Cádiz, the provincial capital, important urban centres are Algeciras, Tarifa, Jerez de la Frontera, and Rota. Railway communication is limited in the west to a line from Sevilla to Cádiz, with branchlines from Sanlúcar de Barrameda to Jerez and El Puerto de Santa María, and in the east to a line from Sevilla to Algeciras. Area 2,871 square miles (7,436 square km). Pop. (2007 est.) 1,207,343.