| Summary : Extensive underground Victorian stone quarries at Corsham, developed 1938-1943 as bomb-proof ammunition depots. By 1943 the Central Ammunition Depot, Corsham, had developed into the largest underground arsenal in the world. Costing over £4,500,000 - an immense sum in those days - it encompassed some 125 acres of subterranean chambers containing 300,000 tons of munitions and explosives. Tunnel Quarry, one of the largest sections, was served by a standard gauge railway off the Great Western Railway. This branch, complete with underground platform and refuge sidings, fed a narrow gauge railway system with diesel locomotives, turntables and workshops. The onslaught of the German air offensive in 1940 caused the various supply ministries to seek protected sites for the manufacture crucial materials such as aircraft engines and weapons. The vast Spring Quarry was requisitioned and converted by the Ministry of Air Production to become the 'largest underground factory in the world'. It was used by the British Aircraft Company to produce Centaurus engines and employed a workforce of over 10,000. In order to brighten their existence the BAC Chairman, Sir Reginald Verdon Smith, commissioned a professional artist, Olga Lehmann, to decorate some of the canteens with vivid murals. By the time the tunnels were operational in 1943 German bombing was no longer a major threat, and they closed two years later. The bill for construction had exceeded £20 million. The site had a valuable second lease of life for a variety of secret Cold War uses, including as a RAF Sector Operations Centre for Southern Sector (mid 1980s). In 1961 a Central Government War Headquarters was constructed that could accommodate the Prime Minister and a nucleus of Ministers and Senior Officials and up to 4000 members of staff. The bunker was fitted with welfare facilities as well as a BBC Studio and telephone exchange. It was equipped throughout the Cold War although never used for its ultimate purpose. |
More information : In response to Zeppelin air raids in World War I, moves were made to develop small underground munitions stores in former mines. The development of heavy bombers in the inter-war period prompted a major push to create huge underground depots. Accordingly, the vast underground stone quarries in the Corsham area of Wiltshire were acquired in 1938 to meet this demand; and by 1943 the Central Ammunition Depot, Corsham, had developed into the largest underground arsenal in the world. Costing over £4,500,000 - an immense sum in those days - it encompassed some 125 acres of subterranean chambers containing 300,000 tons of munitions and explosives. Tunnel Quarry, one of the largest sections, was served by a standard gauge railway off the GWR. This branch, complete with underground platform and refuge sidings, fed a narrow gauge railway system with diesel locomotives, turntables and workshops.
The onslaught of the German air offensive in 1940 caused the various supply ministries to seek protected sites for the manufacture crucial materials such as aircraft engines and weapons. The vast Spring Quarry was requisitioned and converted by the Ministry of Air Production to become the 'largest underground factory in the world'. It was used by the British Aircraft Co to produce Centaurus engines, with part occupied by BSA to manufacture gun barrels. BAC employed a workforce of over 10,000, and to brighten their existence the BAC Chairman, Sir Reginald Verdon Smith, commissioned a professional artist, Olga Lehmann, to decorate some of the canteens with vivid murals.
The Corsham factories were an expensive fiasco - by the time they were operational in 1943 German bombing was no longer a major threat, and they closed two years later. The bill for construction had exceeded £20 million. For the next half century, however, the site had a valuable second lease of life for a variety of secret Cold War uses. (1)
The Corsham Project's website includes an online characterisation study loking at the development of the site from use as a Victorian Quarry therough to its Second World War and Cold War uses. (2)
A Sector Operations Centre was located within a former Second World War operations bunker at ST 850 690.
The United Kingdom was divided into six sectors for air defence purposes. Each was controlled by a Sector Operations Centre (SOC). The SOCs were located within purpose-built underground R4 bunkers, apart from the centres at Box and Longley Lane that were housed in wartime underground operations blocks. The interior of the bunker featured an operations room that occupied the full height of the bunker, with information was displayed on the wall at one end and a large table display on the floor. Control cabins were situated on other three walls overlooking the displays. The upper level cabins were occupied by senior officers and the middle level cabins by the ground executive, which controlled the radar, and the air executive, which directed the airborne aircraft and interceptions. Also contained within the bunkers were rest rooms, lavatories, a kitchen, duty rooms, and rooms for telephone equipment, teleprinters and generators. (3-4) |