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city, Dagestan republic, southwestern Russia. The city lies in the narrow gap between the Caspian Sea and the Caucasus Mountains at their closest approach. Derbent was founded in AD 438 as a fortress to guard the principal caravan route from southwestern Europe to Southwest Asia. It fell to Arabs in 728, Tatars in 1220, and Russians in 1813. Many ancient monuments survive, including the ruins of the 5th-century citadel and an 8th-century cathedral mosque. The modern city's industries include wool spinning and wine making. A large cannery is also located in Derbent. In 2003 the ancient city and its numerous defensive structures were made a World Heritage site. Pop. (2002 prelim.) 100,800