High-angle artillery battery atop Gibraltar’s Rock, guarding against armored warships.
Spy Glass Battery is a high-angle artillery battery on the summit of the Rock of Gibraltar, part of the Fortifications of Gibraltar. Built in the late nineteenth century with six 10‑inch RML guns, it later served in the Second World War as a listening post with Bofors anti-aircraft guns.
Spy Glass Battery, also spelled Spyglass Battery, is a high-angle artillery battery on the summit of the Rock of Gibraltar, within the British Overseas Territory of Gibraltar. Part of the Fortifications of Gibraltar, it was created in the late nineteenth century when thicker battleship armour made conventional coastal guns less effective. Six RML 10‑inch guns were installed as a “retired battery”, placed high on the Rock to increase range and make them harder to hit. The high‑angle Mark 6 RML system was intended to fire shells steeply so they struck a ship’s decks rather than its armoured sides. At these ridge batteries, including Spy Glass, the guns and crews were positioned so low below the surface that only observers could see the horizon, giving the crews considerable protection. The entrance bears the date 1898. During the Second World War the site housed a Bofors anti‑aircraft gun and acted as a listening post, with parabolic devices focusing sound to microphones for early warning of aircraft. Today the remains of Spy Glass Battery are still controlled by the United Kingdom’s Ministry of Defence, and visits require special permission as there are no routine guided tours.
