Annaba (ăn-näbˈə) [key], formerly Bône (bōn), city (1998 pop. 348,554), capital of Annaba prov., extreme NE Algeria, a port on the Mediterranean Sea. One of the country's leading ports, the city is also an important administrative, commercial, and industrial center. The large El Hadjar steelworks, built with French and Soviet financial and technical aid, constitutes the chief industry; others include chemical (superphosphate) manufacturing, food canning, cork production, and railway construction. Founded by the Phoenicians, the city became a favorite residence of the Numidian kings. Under the Romans, it was called Hippo Regius and was a center of early Christianity, the episcopal see of St. Augustine. The city was captured by the Vandals in 431. After the Arab conquest of Algeria in the 7th cent., Annaba became an important Muslim city and port. Spanish forces occupied it in the 16th cent. During the 17th and 18th cent., Annaba was a busy center for European trade. The French took the city in 1832. Landmarks include the Great Mosque and the Cathedral of St. Augustine.