A British overseas territory, disputed by Spain, in the south of the Iberian Peninsula, comprising the Rock of Gibraltar and the sandy isthmus connecting the rock to the Iberian Peninsula. Occupies a strategic position above the Strait of Gibraltar, connecting the Mediterranean Sea with the Atlantic Ocean. A NATO naval base is located on the territory of Gibraltar. Until 2020, Gibraltar was a member of the European Union through the UK’s membership. In 1973, the UK joined the EU along with Gibraltar (but excluding the Channel Islands and the Isle of Man) under Article 299 of the Treaty of the European Community.