Algeciras is a port city in the south of Spain, near the British Overseas Territory of Gibraltar. It is situated on the RÃo de la Miel slightly to the north of Tarifa, which is the southernmost town of peninsular Spain . It is the largest urban area on the Bay of Gibraltar (in Spanish, the BahÃa de Algeciras), with a population in 1999 of 103,106 people.