La Línea de la Concepción (more often referred to as La Línea) is a town in Spain, in the province of Cádiz in Andalucia. It lies on the eastern isthmus of the Bay of Gibraltar on the border with the British overseas territory of Gibraltar, with which it has close economic and social links. It is situated on the sandy isthmus which unites the Rock of Gibraltar with the coast in the eastern flank of the Bay of Gibraltar, between Sierra Carbonera and the Rock of Gibraltar.
The town derives its name firstly from the or boundary line separating Spain from Gibraltar, and secondly from the Immaculate Conception of Mary, the Mother of Jesus. Its people are called in Spanish .
The first dwellings, which date back to the 18th century, were behind the Spanish lines, being part of the Spanish municipality of San Roque until 1870, when La Linea became separate.
The people of La Línea have traditionally found work in Gibraltar, from the days in the 18th century when Gibraltar was an important naval port. This stopped with the total closure of the border by the Spanish government between 1969 and 1982 as a result of the dispute between Spain and Britain regarding the sovereignty of Gibraltar. The border was fully reopened in 1985.
La Línea is a major supplier of fruit and vegetables to Gibraltar; other industries include the manufacture of cork, liquor, and fish paste. It also had an important military garrison with substantial fortifications and a port.