Britain maintains that it is bound by the Treaty of Utrecht of 1713, under which Spain ceded Gibraltar to Britain in perpetuity but which stipulates that if Britain ever withdraws, Spain should have the right to resume sovereignty.

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Until this week, however, these attractions had failed to lure any Spanish government minister to the British territory of Gibraltar for over 300 years (Gibraltar was captured in 1704 and ceded to Britain under the Treaty of Utrecht in 1713).

ECONOMIST: An historic visit, but the same arguments over sovereignty

It is being displayed in the Dutch exhibition to commemorate the 300th anniversary of the signing of the Treaty of Utrecht, which ended the Spanish War of succession in 1713.

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Gibraltar was one: by a treaty signed in Utrecht in 1713, the king of Spain unwisely, but he did it ceded the Rock to Britain.

ECONOMIST: Gibraltar