It announced itself to be " A Treaty of Peace and Friendship between the Most Serene and Most Potent Princess Anne, by the Grace of God, Queen of Great Britain, France, and Ireland, Defender of the Faith, &c. and the Most Serene and Most Potent Prince Philip the Fifth, the Catholic King of Spain, concluded at Utrecht the 2/13 Day of July, 1713", and it meant that Gibraltar ceased to be Spanish and was ceded in perpetuity to Britain.
Many people, however, may not be aware that the same Utrecht treaty went on to give Menorca to Britain as well:
"Moreover the Catholic King doth in like manner for himself, his heirs and successors, yield to the crown of Great Britain the whole island of Minorca, and doth transfer thereunto for ever, all right, and the most absolute dominion over the said island, and in particular over the town, castle, harbour, and fortifications of the bay of Minorca, commonly called Port Mahon, together with the other ports, places, and towns situated in the aforesaid island. But it is provided, as in the above-written article, that no refuge or shelter shall be open to any ships of war of the Moors in Port Mahon, or in any other port of the said island of Minorca, whereby the Spanish coasts may be infested by their excursions: and the Moors and their ships shall only be allowed to enter the island aforesaid on account of traffic, according to the agreement of treaties."
Following the signing of the Utrecht Treaty Spain almost immediately regretted it. It made several attempts to get Gibraltar back, by different means, and would still like it to be returned today, but the Gibraltarian people insist they want to remain British and they are supported in that by the UK government.
Menorca, however, had a much more chequered history. It was first returned to Spain under the Treaty of Versailles in 1783. They had been a frenetic 70 years: the British temporarily lost the island to France in 1756, during the Seven Year War, but regained it under the Treaty of Paris in 1763 after winning that war. In 1782 Spain regained control of Menorca after a lengthy siege in Port Mahon, and Britain ceded it back to Spain the following year. That however, was still not the end of the matter. The small island of Menorca was invaded by the British once again in 1798, during the French Revolutionary Wars, but it was finally and permanently repossessed by Spain under the Treaty of Amiens in 1802.
The Utrecht Treaty of 13 July 1713 changed history, but as everyone knows, the course that history will take can never be predicted.