Fort Malborough was conceived as an auxiliary fortress to support San Felipe castle, built at the mouth of the port of Mahon. Its name comes from the most famous British general, Sir John Churchill, Duke of Malborough (the Malborough of the song ‘Marlbrough s'en va-t-en guerre’ in French and ‘Mambrú se fue a la guerra’ in Spanish).
The fort includes an underground area with rooms, moats, mines and countermines, plus a central, open air section with bastions where artillery and infantry were placed for defence and the south-east section of the San Felipe castle. It was refurbished several times during the 18th century until it was partially demolished by Spanish troops. It was finally recovered by the Rubió Tudurí-Andrómaco Foundation, which in turn sold it off to the Consell Insular de Menorca (Minorca Council) for refurbishment and conversion into a military history interpretation centre in the port of Mahon.
Fort Malborough participated in the siege by the French army under the command of the Duke of Richelieu in 1756, who ultimately conquered the island for France and occupied it between 1756 and 1763. It was also besieged by the Spanish army in 1781, with the Duke of Crillón at the helm, who briefly returned Minorca to the Spanish crown in 1782.
The Fort is manned by one captain, 50 infantrymen and 15 gunners. The infantrymen defended the moat from the embrasures, while the gunners manned the cannons on the top platform. The fort has an interesting exhibition that uses technology to transport visitors to the 18th century.