Hawthorn, Wiltshire

Hawthorn is the location of a number of defence related underground facilities in the vicinity of Corsham, Wiltshire. Specifically the Hawthorn site was the location of an above-ground bunker used for the planning of satellite communications support to the United Kingdom's armed forces worldwide. These facilities had been built in quarries cleared through the excavation of Bath stone. The quarries have variously been used for Military Command & Control, storage, and the emergency fallback seat of the national government. Some areas of the quarry complex were hardened and provided with support measures to ensure resilience in the event of an enemy nuclear attack.

Central Ammunition Depot

Main article: Monkton Farleigh

During the 1930s, there was a recognition of a need to provide secure storage for munitions across the United Kingdom. The proposal was to create three Central Ammunition Depots (CAD): one in the north (Longtown, Cumbria); and one in the Midlands (Nescliffe); and one in the south.

The easily-hewn Bath stone, a form of lime stone, had created a number of large, horizontal, and relatively dry quarries around the Corsham. Monkton Farleigh quarry was renovated from the late 1930s by the Royal Engineers as one of the three major stockpiles.

In November 1937 the Great Western Railway were contracted to build a 1,000 feet (300 m) long raised twin-loading platform at Shockerwick, with two sidings from the adjacent Bristol-London mainline branching off just outside the eastern entrance to the Box Tunnel at 51°24′19.31″N 2°17′22.94″W. 30 feet (9.1 m) below and at right angles to this point, the MoD had built a narrow gauge wagon sorting yard. This was attached by a 1.25 miles (2.01 km) tunnel built by the Cementation Company, descending at a rate of 1:8.5 to the Central Ammunition Depot, housed in the former mine workings. The whole logistics operation was designed to cope with a maximum of 1,000 tonnes (1,100 tons) of ammunition a day.

The narrow gauge trucks would descend from the platform to the tunnel, where a heavy-duty conveyor belt (the depot was either taking in ammunition or putting out, never both at the same time), would propel the ammuntion directly to the appropriate storage gallery. The construction design meant that an explosive accident or detonation inside any one of the stores would not propagate throughout the ammunition storehouse. The conveyor belt, and the original cable-way used as a temporary instalation while the tunel was being built, ran 24/7 for 30 days in the run-up to D-Day.

CAD Monkton Farleigh closed at the end of hostilities, although was kept in an operational condition until the 1950s. The sidings were then cleared, and not used again until the mid-1980s when a museum opened for s short period on the site. Today the north end of the tunel is sealed by a concrete and rubble instalation, while the former mine/CAD is used for secure commercial document storage.

Aircraft Engine Factory

A portion of the quarry complex was developed as an aircraft engine factory, to act as a fallback should the Bristol Engine company factory at Filton be taken out of action by bombing. This engine factory was never used.

Royal Air Force Rudloe Manor

Main article: RAF Rudloe Manor

In another area of the quarry Royal Air Force Box was established as the Headquarters of the 10th Fighter Group of the Royal Air Force. RAF Box was later renamed RAF Rudloe Manor and expanded to encompass a number of communications functions including No1 Signal Unit, Controller Defence Communications Network, No1001 Signal Unit Detachment and Headquarters RAF Provost & Security Service.

No1SU and CDCN were both housed in bunkers within the quarry complex, which also included an RAF Regional Command Centre for the South West of England.

Adjacent Defence Establishments

In the vicinity of Hawthorn were Basil Hill Barracks, a Royal Signals establishment, HMS Royal Arthur, a Royal Navy training establishment and the Royal Naval Stores Depot Copenacre which used the quarries as a storage facility. Corsham Computer Centre was built into Hudswell Quarry during the 1980s.

The Army Welfare Service Cotswold Families Centre is to the south.

Seat of national government

Main article: Central Government War Headquarters

British defence doctrine during the early Cold War period indicated a requirement for a fallback location for central government outside London, to assume national control in the event of London being destroyed. The quarry complex at Corsham was chosen for this location and development of the site commenced in the 1950s. In the event of imminent nuclear attack, it was assumed that the government would be evacuated from London by rail or helicopter. The facility would provide a safe haven for the Prime Minister, Cabinet, commanders of the Royal Air Force, Royal Navy, and British Army and supporting civil servants and military personnel.

The site had a number of code names during its lifetime: Stockwell, Subterfuge, Burlington, Turnstile, Chanticleer and Peripheral.

Facilities inside the complex included accommodation and catering for nearly 4,000 people, including a hospital, self-contained electrical generation equipment, and the ability to seal off the complex from the outside environment, which could be contaminated by radiation, poison gas or other threat.

In practice the use of the facility would have required planning and a controlled migration since the warning times of an unannounced nuclear attack preclude mobilisation out of London, though this would have been more likely to be done late in the crisis phase.

The site was taken over by the Ministry of Defence in 1991 following the fragmentation of the Soviet Union and the end of the Cold War, though it was kept on standby in case of future nuclear threats to the U.K. Finally, in December 2004, with its underground reservoir drained, emptied of fuel and supplies, and with a skeleton staff of just four, this site was decommissioned and abandoned.

Disposal

The Hawthorn site has been offered for sale, conditional on a Private Finance Initiative for the continued use of the above-ground facilities.

Further reading

• Hennessy, Peter (2010). The secret state : preparing for the worst, 1945-2010 (2 ed.). London: Penguin. ISBN 978-0-141-04469-9. 
• McCamley, Nick (2000) Secret underground cities : an account of some of Britain's subterranean defence, factory and storage sites in the Second World War, Pen & Sword Books Ltd, ISBN 0-85052-733-3

External links

• BBC Wiltshire: Burlington Wiltshire's Underground City
• Britains Cold War - Guide to the Cold War in Britain
• Subterranea Britannica
• Nettleden site - Informative site with many pictures
• UK Secret Bases Full features (April 2007) on
• Aerial photo of Hawthorn, Wiltshire. Other map and aerial photo sources.
• 1999 article by Hugh Collins at former CorshamNet

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