The Battle of Mount Longdon was an engagement of the Falklands War between the British Third Battalion, of the Parachute Regiment supported by six L118 light guns and the Type 21 frigate, . Argentine forces consisted of the 7th Infantry Regiment with other attached elements. The engagement took place on 11-12 June 1982 and was one of three battles in a Brigade-size operation all on the same night, the other two being the Battle of Mount Harriet and the Battle of Two Sisters.