Secret WWII Cave

Come and visit the Gibraltar’s Top Secret WWII Cave, created under Operation Tracer  during WWII,  locally known as Stay Behind Cave. Only 40 individuals are allowed to visit per year!

Secret WWII Cave

Stay Behind Cave – Operation Tracer

Operation Tracer was a secret Second World War military operation in Gibraltar. The driving force for the idea was the 1940 plot by Germany to capture Gibraltar, codenamed Operation Felix. 

Operation Tracer was the initiative and idea of Rear Admiral John Henry Godfrey, the Director of the Naval Intelligence Division of the Admiralty.

In 1941, Godfrey created the covert observation post that would remain operational, even if Gibraltar fell to the German. 

The post was to be used to report on enemy capability and movements within the harbour for Intelligence purposes. Godfrey went to seek the assistance of several distinguished consultants to bring the plan to life. It was such a secret plan that Godfrey held meetings with the consultants at his private residence rather than at Whitehall.

After considering various locations, the post was constructed using the tunnel structure of Lord Airey’s Shelter, the underground military HQs just north of Lord Airey’s Battery. This artillery battery is located at the upper ridge of the Rock of Gibraltar, near the southern end of what is now the Upper Rock Nature Reserve.

Six volunteers were selected for the operation, including an executive officer, two physicians and three wireless operators. The men had volunteered to be sealed inside the cave should Gibraltar fall to the Nazis.

The volunteers fully understood that they would possibly need to remain sealed in the cave for about a year. The shelter had provisions for a much more extended stay, up to seven years if required.

Fortunately, there was never the need for the Allies to use this post. As a result of the Nazi Empire collapsing,  the Director of Naval Intelligence ordered the plan to be aborted. The provisions in the complex were distributed, and the cave closed.

Rumours of a secret post, eventually nicknamed Stay Behind Cave, circulated for decades in Gibraltar until its discovery in 1997 by the Gibraltar Caving Group. 

The site’s authenticity was confirmed in 1998 by one of the builders, and a decade later, it was also confirmed by one of the physicians, who also was the last surviving member of the Tracer team, who in 2010 died.

The Discovery of the WWII Secret Cave

Since World War II, rumours circulated of a secret complex inside the Rock of Gibraltar. For decades, historians and enthusiasts explored the Rock’s cliffs, tunnels, and caves, but to no avail. However, in late 1997, after more than two years of searching, the Gibraltar Caving Group unearthed a secret post in an area close to Lord Airey’s Battery at the Upper Ridge of the southern end of the Upper Rock of Gibraltar. The Caving Group had evaluated the potential locations of the post. It concluded that it had to be located at a high place on the Rock to command good views of both the Mediterranean and the Bay of Gibraltar.

Their theory was confirmed when members of the group felt a rush of wind in a tunnel were exploring. Further detailed exploration revealed a wall into a series of chambers. It was immediately recognised that the secret cave complex was likely to be the legendary site of Operation Tracer. Locals know the hidden secret observation post as the legendary Stay Behind Cave.

Secret WWII Cave - Stay Behind Cave

After the Caving Group felt the draught of wind in the tunnel, they pushed aside some corrugated metal sheets and found a bricked-in area of the wall. 

The caving group carefully removed some bricks, soon revealing a doorway behind the bricked-in area of the tunnel. The caving group also discovered the observations posts, including a concrete slab on the west. The Caving Group also the remains of a bicycle. They also found tubing that sheathed the aerial rod along with the steps. The complex had Cork tiles located on the floor, which would have provided insulation (warmth and sound). 

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