Hole in the Wall Battery, also known as Cliff Battery, occupies a commanding position on the edge of a sheer precipice overlooking the southern approaches to Gibraltar. Its elevated location provided an excellent field of fire over both the coastline and sea below, making it a key component of the southern defensive line at Windmill Hill.

The origins of the site date back to the late 18^th or early 19^th century, when it formed part of the wider defences of Windmill Hill. It was originally equipped with RML (Rifled Muzzle Loading) guns, designed to prevent any enemy landing from the south. The pivot and racer of one such gun remain visible today, embedded in the rock. Cliff Battery was also referred to as No. 1 Emplacement.

However, after 1860, the individual emplacements were designated by letters instead and extended from A Emplacement, located near the military prison on the western side, to R Emplacement at Hole in the Wall on the eastern side. Along the eastern side, there were five emplacements fitted with pivots and racers, likely intended for the 68-pounder guns, extending from R Emplacement (Hole in the Wall Battery) to Buffadero. Beyond these, there were twenty-seven additional positions, all constructed as platforms for standing garrison carriages. Initially, not all of these emplacements were armed or occupied, and R Emplacement was shown as having no armament on site. However, the 1884 armament list shows a single 80-pounder RML gun located at this position. The gun was still there in 1889.

At the turn of the 20^th century, there was a proposal to mount two 12-pounder Quick-Firing (QF) guns at Cliff Battery, though this plan was never implemented.

Although the wartime records do not explicitly list a position named “Cliff,” it is believed that this site corresponds to that designation, due to its location on the edge of a steep cliff and its clear tactical advantage. Supporting this theory is the fact that the name “Hole-in-the-Wall” was already in use for a nearby infantry post on the Commercial Hole, suggesting that the artillery position had to be given a distinct name—hence, “Cliff.”

Map of Gibraltar's WWII defences showing the site of the R Emplacement.

Defensive wall along the Upper Europa Flats cliffs.

The site was adapted for modern defence in July 1940, at the start of WWII and fitted with a Bofors 40 mm Light Anti-Aircraft (LAA) gun and a predictor plinth. The site was again designated as R emplacement of the Windmill Hill Batteries. The 40 mm Bofors gun was one of four that had arrived in Gibraltar on the 27^th June 1940 with the 82nd Heavy Anti-Aircraft Regiment. It remained operational until the 12^th February 1944, after which it was left unmanned. The gun and associated equipment were removed in May 1944, although the site itself continued to be maintained.

A cement plaque at the entrance reads:

“9 LAA Bty 3 LAA Regt ELAA 1939”

However, this inscription is slightly inaccurate, as the gun was not installed until 1940, and the 3rd Light Anti-Aircraft Regiment was not formed until June 1941.

Practice firing of the 40 mm Bofors took place at the site in 1954, but the gun was removed shortly afterwards, certainly by 1956.

Today, the remains of both the Victorian RML emplacement and the WWII Bofors can still be found on site.

R Emplacement, Map-34-Sheet-30 Windmill-Hill Barracks,1941.