Ramblers uncover secret war bunker
The Times, 27-9-2014
Simon Tait
The entrance to a hole in the ground in a Wiltshire woodland is hardly visible, even after the undergrowth has been cleared away from the rusted metal grill, but it is the gateway to a Britain where Nazi Germany has invaded, where ordinary civilians have become underground guerrillas, nocturnal saboteurs and spies, where clandestine radio stations are manned by female officers, reportedly nicknamed “Secret Sweeties”.
Germany’s invasion never came, but the largest of the subterranean radio stations in the intelligence network set up in the Second World War – “Super Zero Station” – has been discovered and has been scheduled as an ancient monument by English Heritage to protect it.
“The role of the Auxiliary Units in the Second World War is one of the relatively little understood and untold chapters in our national history,” said Tony Calladine, acting head of designation at English Heritage. “Those men and women who were trained to resist invading forces in what would have been its darkest hour, for little or no recognition, are celebrated in this designation.”
So secret was the system that eventually covered the coasts south and east from Cardiff and north to Caithness that little detail is known about the GHQ Auxiliary Units (Aux Units) set up by Winston Churchill in 1940 before the Battle of Britain, and even less about the men and women who served in them. Their existence was “Most Secret” and kept on a “need to know” basis.
Aux Units was divided into two sections, the Operational Branch guerrillas (Ops) who were largely civilians specially trained and living in underground bunkers of which over 1,000 are thought to have been made; and the Special Duties Branch, the vital communications system in 155 stations manned largely by women in the Auxiliary Territorial Service, of which the station uncovered in Wiltshire is the most refined.
Those who served were never recognised for their work, though they were kept in continual readiness until after D-Day in 1944, fully aware that if caught they would be handed to the Gestapo. Ops recruits were enlisted into the Home Guard and could eventually claim the Defence Medal, but the 3,250 Special Duties civilians could not.
The British Resistance Archive, which seeks out Aux Units survivors and their families, has managed to help many get their medals and also included some surviving volunteers in the 2013 Armistice Day parade at the Cenotaph for the first time. Its founder, Tom Sykes, hopes some wireless operators may join the parade this November.
There were 125 out-stations from which operators in the community would send their information, many of them in mundane hiding places such as in bell towers, down wells or inside church altars. One sophisticated outstation complete with maproom has been found intact under an outdoor Devon privy, accessed with the help of a bewildering complex of pulleys, counter-balances and switches.
Their messages would go to one of 30 in-stations, or Zero Stations, operated by the “Secret Sweeties”, Auxiliary Territorial Service (ATS) officers. Their ATS commander, Beatrice Temple, writing in her personal diary, called the Wiltshire base the “Super Zero Station”, and The Times has been asked not to identify its whereabouts. Super Zero is between three and four metres deep, three metres wide and 10.3 metres long – three times the size of other Zero Stations, the whereabouts of half of them are already known. Its escape tunnel is 22m long.
David Hunt, a retired Royal Signals colonel who has made military archaeology his speciality knew of the existence of Super Zero from references in policy documents held in the National Archive, but not its whereabouts until local woodland walkers stumbled on it a year ago and Col Hunt was alerted. He knew immediately what it was and applied to English Heritage for its protection from treasure hunters.
“We had been building these underground stations since 1940 and this one was not made until about 1943,” said Col Hunt. “It was the ‘best of breed’, the most sophisticated, and they had to be concealed so that anyone walking above would be unaware of what was beneath their feet. Whereas most in-stations would be manned by three ATS officers, this one could have accommodated nine, and would have had a generator and been provisioned and with enough fuel for 21 days, completely closed down. The dugout had various layers of security for the entrance and a 30 m escape tunnel together with a sophisticated ventilation system.”
Super Zero was part of an “inner network” serving HQs up to Army Southern Command, controlling the south-west corner of England, nothing operational was written down in the interests of secrecy, and the specially adapted VHF wirelesses. Its aerial leads were concealed inside the bark of nearby trees.
But the Super Zero’s contents have still not been examined. “This control station in Wiltshire is particularly rare and fragile, to the point where we could not gain access to the interior”, said Mr Calladine. “These structures are dangerous and should not be sought out, especially on private land where trespass is illegal”. This particular one is also thought to have dangerous asbestos and to have become the habitat of protected bats and needs to be made safe before it can be examined, but in consultation with the owners of the property English Heritage intends to examine Super Zero as soon as possible
Aux Units was kept at readiness throughout the Second World War until after D-Day, and in July 1944, Special Duties were quietly disbanded. But their burrows were not destroyed; their entrances were concreted over and concealed so that the special construction and security techniques developed over four years would not become public – in case they might need to be used somewhere in the uncertain post-war future. The special wireless sets, designed by radio amateurs serving in Royal Signals, were all removed and destroyed to keep their “privacy technology” and no records survive. Even today the secrets of how it worked are still not fully understood.
“We can only speculate about what was in Churchill’s mind, but war is unpredictable and no-one knew what would happen, or even who the invaders eventually might be,” said Col Hunt. “These were left, operable but with their equipment removed, so that what had been achieved was not forgotten, and just in case.”
“We continue to protect, where appropriate, structures that tell fascinating stories related to many aspects of our national heritage, some of which are featured and explained on our Heritage Highlights pages (https://www.english-heritage.org.uk/caring/listing/showcase/heritage-highlights/),” said Mr Calladine.
