Disputed status of the isthmus between Gibraltar and Spain
Coordinates: 36°09′08″N 5°20′43″W / 36.152336°N 5.345199°W
The Gibraltar territory currently contains an 800-metre (2,625 ft) long section of the isthmus that links the Rock with mainland Spain. Spain does not acknowledge British sovereignty over Gibraltar beyond the fortified perimeter of the town as at 1704. The United Kingdom claims the southern part of the isthmus on the basis of continuous possession over a long period.
As well as the airport, there are two substantial housing estates, a sports stadium, a secondary school, a marina, and a beach on this land, which de facto is an integral part of the territory of Gibraltar.
One of the sources of the dispute is the lack of appropriate definitions of what had been actually ceded to Great Britain. The Treaty of Utrecht did not include any map or specific description of the ceded elements, so that is subject to different interpretations from each side. According to Article X of the Treaty of Utrecht, dominion is ceded over the town and castle of Gibraltar, together with the port, fortifications, and forts thereunto belonging.
Spain does not acknowledge British sovereignty over Gibraltar, as they consider that the only part that was ceded was the fortified perimeter of the city, and the rest had no territorial jurisdiction (the literal phrase of the treaty is "the Catholic King wills, and takes it to be understood that the above-named propriety be yielded to Great Britain without any territorial jurisdiction"). Therefore, the Treaty would not have ceded any part of the isthmus. Spain considers that such an area was occupied by the UK since the 19th century (1815), and such "occupation of the isthmus [by the United Kingdom] is illegal and against the principles of the International Law". For said reason, British sovereignty is not acknowledged by Spain, considering itself instead to be owner of the territory (see map).
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