The Military Heritage Centre is housed at Princess Caroline's Battery, a former artillery battery located at the northern end of the Gibraltar Nature Reserve, Upper Rock, above the Moorish Castle. It was constructed in 1732 and named after the third daughter of King George II. The battery saw action during the Great Siege of Gibraltar and required repairs. In 1871, the battery featured a 9-inch rifled muzzle loading gun, with an Elswick Ordnance Company carriage and platform.
In 1905, the battery was refurbished to accommodate a 6 inch Mark VII gun that was installed on top of the magazine. While the battery has been decommissioned and the gun removed, the same hoists that were utilised to arm the weapon are still present. The explosive charges that propelled the 6 inch gun's shells were housed in a room with three small interior windows. Lanterns in the windows illuminated the cartridge storage chamber without the risks inherent with an open flame.
The explosive charges were passed through the dispensing hatch at the floor level and were then raised by a hoist to those manning the gun. In order to avoid the danger of an inadvertent explosion caused by a spark, soldiers changed their clothes in an adjacent annex, and even wore special footwear. The Military Heritage Centre at Princess Caroline's Battery is a small underground exhibition centre. In addition to relics from the battery, the facility is home to the Memorial Chamber.
The relics exhibited date from the eighteenth century to the present, and include weapons, shells, and other artefacts. The Memorial Chamber features the roll call of those regiments deployed to Gibraltar since the early eighteenth century. In addition, the ensigns of the Royal Air Force and the Royal Navy are displayed in the Memorial Chamber. There is also a monument which commemorates British Regiments.