36°09′18″N 5°20′54″W / 36.154933°N 5.348363°W
The Gibraltar–Spain border is the international boundary between the British Overseas Territory of Gibraltar and the Kingdom of Spain. It is also referred to as "The Fence of Gibraltar" (Spanish: La verja de Gibraltar) or simply "The Fence".
Gibraltar (/dʒɪˈbrɔːltər/ jih-BRAWL-tər, Spanish: [xiβɾalˈtaɾ]) is a British Overseas Territory and city located at the southern tip of the Iberian Peninsula, on the Bay of Gibraltar, near the exit of the Mediterranean Sea into the Atlantic Ocean (Strait of Gibraltar). It has an area of 6.8 km (2.6 sq mi) and is bordered to the north by Spain (Campo de Gibraltar). The landscape is dominated by the Rock of Gibraltar, at the foot of which is a densely populated town area. Gibraltar is home to around 34,000 people, primarily Gibraltarians.
Gibraltar was founded as a permanent watchtower by the Almohads in 1160. It switched control between the Nasrids, Castilians and Marinids in the Late Middle Ages, acquiring larger strategic clout upon the destruction of nearby Algeciras c. 1375. It became again part of the Crown of Castile in 1462. In 1704, Anglo-Dutch forces captured Gibraltar from Spain during the War of the Spanish Succession, and it was ceded to Great Britain in perpetuity under the Treaty of Utrecht in 1713. It became an important base for the Royal Navy, particularly during the Napoleonic Wars and World War II, as it controlled the narrow entrance and exit to the Mediterranean Sea, the Strait of Gibraltar, with half the world's seaborne trade passing through it.
La Línea de la Concepción (Spanish pronunciation: [la ˈlinea ðe la konθeβˈθjon]), often referred to simply as La Línea, is a municipality of Spain belonging to the province of Cádiz, Andalusia.
The city lies on the sandy isthmus which is part of the eastern flank of the Bay of Gibraltar, and it limits with the Gibraltar–Spain border to the south. La Línea has close economic and social links with the British overseas territory of Gibraltar. It is part of the comarca of Campo de Gibraltar.