Operation Tracer - Stay Behind Cave

An article on the secret complex hidden inside the Rock, built to spy German troops and equipment movements in the event of the Rock falling into enemy hands during WW2.

by Neill Rush

3D Views on Stay Behind Cave layout Click on thumbnails to view larger image

All around the World, different countries and places have tales of mystery and intrigue, legends and stories that fuel the imagination. Gibraltar is no different to the others. Recollections and rumours from locals and servicemen about ”Operation Tracer” or “Operation Monkey” (as it was locally known,) have persisted through the years about this potentially suicidal World War Two plan. But a few years ago the members of the Gibraltar Caving Group found the actual site, mystery solved? Not really, because there is still a lot of information missing and that probably will remain so for many years to come.

The story of the Stay Behind Cave (also sometimes referred to as Braithwaite’s Cave after Major Braithwaite who led the team building the complex, and who in fact died when a tunneling charge went off accidentally) has been told to visitors on the popular Second World War tunnel tours for many years. Tales of how volunteers would brick themselves into rooms dug out of the tunnel walls to monitor German troops and equipment movements in the event of the Rock falling into enemy hands. The rooms would be equipped with radios and all the necessary supplies to enable the men to carry out their task. It was said that a bath of lime would be installed, so that if any of the servicemen died they would be placed in the bath, which would dissolve their remains and eliminate any smell. When the final occupant of the cave met the same fate it would not really matter. The only thing about this was that the location the tourists were shown would not provide the required field of vision needed for monitoring events. The Gibraltar Caving Group analyzed where they thought the cave should be, if it still existed, and agreed that it had to be high up because it would need to have an excellent view of both the Mediterranean and the Bay across to Algeciras.

Records released show that British Intelligence planned, in 1941, to seal six men inside the Rock of Gibraltar in the event that it fell to the Nazi forces. The plan was devised shortly after the fall of France and sources indicated that the German Forces were about to make an attempt to move through Spain and take the strategically placed Rock.

It was decided to construct the cavern system high up inside the existing tunnels to provide a spy position to monitor the German ship movements. Potential volunteers were told that if accepted they would be bricked up in the cave and that they would have no way out.

An expert on survival techniques, George Murray Levick, who had been on Scott’s expedition to the Antarctic was recalled by the navy, at the age of 64, and given the rank of Surgeon Commander to advise on how to exist in such conditions. They were to be given enough supplies to last them for seven years and Levick’s role was to advise on psychology, diet exercise, recreation and the use of alcohol and tobacco. Also he was tasked with suggesting the correct clothing for the men, ventilation of the cave, sanitation and how to deal with those who died, “by embalming and cementing up”. It also is recorded that Levick actually spent seven months in an igloo, alone, and recalled how he used to hallucinate about walking down a street full of sweet shops, but it was always in the afternoon, and it was half day and early closing.

This plan was in fact so secret that no discussions took place in Whitehall, they were conducted at 36, Curzon Street, Mayfair the home of Admiral John Godfrey the then Director of Naval Intelligence. Construction work was conducted in secret so that even the men involved in the tunneling were unsure of its exact location. All of the workers involved were immediately posted back to England after completion of the project and not deployed overseas again for fear they might reveal the existence of the plan.

One day, back in 1997, the members of the Gibraltar Caving Group, Mark Ainsworth, Ian Bramble, Richard Durrell and Jean-Paul Latin were high in the tunnels when they noticed a draught coming from one of the tunnels walls. It was strange; it had to be coming from somewhere. Upon investigation, after making a small opening, they found a brick wall and behind this they noticed the wooden frame of a door leading to a previously undiscovered tunnel. Entering into the darkness they realized what they had found.

Entrance to cave

It wasn’t just a cave it was a complete purpose-built tunnel system within the existing tunnel system. Elation was not the word; they had discovered “Stay Behind”. The myth had been exploded and for three months they kept the existence and actual location a closely guarded secret, while they conducted further research.

One day, back in 1997, the members of the Gibraltar Caving Group, Mark Ainsworth, Ian Bramble, Richard Durrell and Jean-Paul Latin were high in the tunnels when they noticed a draught coming from one of the tunnels walls. It was strange; it had to be coming from somewhere. Upon investigation, after making a small opening, they found a brick wall and behind this they noticed the wooden frame of a door leading to a previously undiscovered tunnel. Entering into the darkness they realized what they had found.

Entrance from inside

The floor of the main hall had been covered in cork tiles to reduce any noise and to provide some insulation and it was of sufficient dimensions to permit the men to exercise. At one end of the room, in the walls, they found a 10,000-gallon water tank filled from a water catchment high in the Rock. There was a brass tap in the wall with an area where the water could drain away naturally. When eventually they managed to turn the tap on, what came out was a thick sludge, but after a short while, it became clear cool water. On one occasion the tap was left running for six hours and the following day the tank was found to be full again (Good British Workmanship!).

Tap and drainage

The floor area nearer the entrance was found to be covered in loose soil and rubble; it is thought that this was where, if necessary, they would have buried the dead. Going on from the main room towards a set of steps, the toilet area was discovered and opposite was what used to be the radio room. By the side of this room were the rusting remains of a bicycle A leather strap, probably to cut down on noise, had been used to replace the standard drive chain. This was used as a generator to recharge the radio batteries (and to give the men some other form of exercise). When it was the prearranged time to send their signal, to avoid any interference with contact with the rock, the aerial was fed down through an asbestos pipe. Immediately after the broadcast the aerial was brought back into the complex.

The steps led up to what is now known to be the Eastern Observation Post (OP), from here it was possible to monitor shipping for miles, also at this OP it was possible for the men to clamber out on to a small ledge, where undetected, they were able to be in the fresh air. Halfway up these steps was another set leading to the Western OP; here there was a very small slit, which gave excellent views of the bay and the shipping that would have been present. On the ground there was a small slab of concrete that was used to block up the slit so that it became invisible from the outside. Incidentally when the group were trying to write some notes one day, the light from the open slit shone on to the piece of paper, and acting like a pinhole camera, projected a picture of the bay on to it.

Conditions would have been spartan inside to say the least. There would have been accommodation for probably six-men, all volunteers, comprising of an Officer, a Surgeon and four Signalers (all who would have had their appendix and tonsils removed before going into the cave). Lighting, it is thought, would have been from fat burning lamps, so as not to give off any smell, and food would have consisted of something like chemically heated soups, dried rations and powdered foods. It would certainly have been claustrophobic living in such conditions with five other men, so it is thought that strict psychological vetting would have been used in the selection of the candidates to ensure they were of the highest quality with stable characters.

The individual names of the men are not known, all were probably Royal Navy, but it is suggested that Surgeon Lieutenant’s Cooper and Milner of the RNVR could have possibly been involved, as they are listed as being attached to HMS Cormorant on the orders of the First Sea Lord. Others were trained at the Naval School in Shotley, Suffolk before being sent to Gibraltar with ”Proper Jobs” as a cover for the real purpose of their assignment. It was not until August 1943, with the pressure on the new “Eastern Front” and the redeployment of the German Forces that it was decided to put the operation on ice. However further records show that very similar Tracer type operations were also planned for Malta, Colombo, Trincomalee and Aden.

No manuals or papers on the operation have ever been found, indeed if they ever existed. Reports say they did, but what we don’t know now will most likely remain a secret forever, unlike “Stay Behind Cave” itself.