Algeciras (Spanish: [alxeˈθiɾas] ) is a city and a municipality of Spain belonging to the province of Cádiz, Andalusia. With a registered population as of 2020 of 123,078, it’s the largest municipality of the Campo de Gibraltar and the second largest in the province. The city is located in the western shore of the Bay of Gibraltar (Bahía de Algeciras) opposite the Rock of Gibraltar, around the mouth of the Río de la Miel, now mostly culverted in its lower course near the southernmost end of the Iberian Peninsula and continental Europe and the Strait of Gibraltar.
The area was inhabited in Antiquity, including archaeological strata generally identified with the Roman city of Iulia Traducta. Founded soon after the Islamic conquest of the Iberian Peninsula on the mouth of the Río de la Miel, al-Jazira al-Khadrā became the head of a rump taifa kingdom after Umayyad state collapse in the 11th century. In 1275, the Emirate of Granada ceded the place to the Marinids, who founded the new walled precinct of al-Bunayya after 1282 on the opposite bank of the Río de la Miel. The twin medinas were conquered in 1344 by the Crown of Castile. Medieval urban continuity came to an abrupt end when the town was torn down by the Nasrids circa 1369–1385. The ruins were repopulated and the town eventually refounded upon the arrival of refugees from the 1704 Anglo-Dutch capture of Gibraltar.