MEDINA SIDONIA, a town of Spain, in the province of Cadiz, and about 21 miles by road westward from that city, stands at a height of 600 feet above the sea-level, on an isolated hill surrounded by a cultivated plain. Apart from its picturesque airy situation it has nothing to interest the traveller; the streets are narrow, steep, and dirty, and its buildings and ruins are unimportant. The occupations of the inhabitants are connected chiefly with the agriculture and cattle-breeding carried on in the surrounding district; bricks and pottery are also made to some extent. The population in 1877 was 12,234.

Medina Sidonia has been identified by some with the Asiao of Pliny, but it is uncertain whether Jerez is not more probably the locality referred to by that name. Under the Visigoths the place was erected into a bishopric (Assidonia), and attained some importance; in the beginning of the 8th century it was taken by Tarik. In the time of Edrisi the province of Shaduna or Shidona included, among other towns, Seville and Carmona; later Arab geographers place Shaduna in the province of Seville. The town gives its title to the ducal house of Guzman el Bueno, the hero of Tarifa (1292).