Cádiz (Spain) (ancient Gadir; later Gades), city and seaport in southern Spain, capital of Cádiz Province, on the Gulf of Cádiz (an inlet of the Atlantic Ocean), near Gibraltar. It lies at the tip of a narrow isthmus that forms the western boundary of Cádiz Bay. The large harbor is divided into an outer bay and a nearly landlocked inner harbor.

During the 20th century Cádiz grew as a base for the shipping, shipbuilding, and fishing industries. A Spanish military base is located in the city. A large part of Spain's trade with the countries of South and North America moves through Cádiz. Exports include sherry wine, cork, olives, figs, salted fish, and salt. Machinery, iron, coal, timber, coffee, cereals, and other foodstuffs are the major imports. Tourism is important to the local economy.

Cádiz is a picturesque city, with white buildings in the Moorish architectural style, and with beautiful promenades. It has a cathedral dating from the middle of the 13th century. In the Church of Santa Catalina is the unfinished painting Marriage of Saint Catherine, by the Spanish artist Bartolomé Esteban Murillo, who fell and died while working on the painting. The medical school of the University of Seville, a navigation school, and a theological school are here. Valuable Roman and Carthaginian antiquities are on exhibit in the Cádiz Archaeological Museum.

The ancient Phoenicians founded Cádiz, one of the oldest cities in Europe, by the 8th century BC. By 700 to 600 bc it was a flourishing market for amber and tin. The Carthaginians captured the city about 501 bc and lost it to the Romans at the end (206 bc) of the Second Punic War (see Punic Wars). The city was destroyed by the Visigoths in the 5th century ad. In 711 it was taken by the Moors, who rebuilt it. Alfonso X, king of Castile and Léon, captured the city in 1262.

After the voyage of Christopher Columbus in 1492, Spanish fleets carrying treasure from the Americas used Cádiz as a base, and it became one of the wealthiest cities of Europe. After the other maritime powers of Europe began to challenge Spanish naval supremacy, Cádiz was subjected to frequent attacks. An English naval force under the navigator Sir Francis Drake raided the port in 1587, destroying many vessels, and in 1596 the city was plundered by an English fleet commanded by Robert Devereux, earl of Essex.

During the next 100 years British naval forces attacked Cádiz on three occasions. It was blockaded by a British fleet for nearly 15 months in 1797 and 1798. During the Napoleonic Wars (1799-1815), Cádiz was besieged by French naval forces from February 1810 to August 1812. Following the loss of the Spanish colonies in the Americas in the 19th century the prosperity of the city declined. During the Spanish Civil War (1936-1939) Cádiz was used as a base by the Nationalist forces under General Francisco Franco. Population (2007) 128,554.