Civil Defence today

Last Updated: 15th October 2024

Corsham Quarries and Bunkers

Corsham has a fascinating history with quarrying in the area starting in about the 1840s as an operation by the Bath and Portland Stone Company. Quarrying still takes place today at Hartham Park Quarry which also had connections with the Copenacre Quarry to the North.

The Corsham area had a number of different Quarries and during World War 2 many requisitioned by the MOD and some have remained in MOD control ever since! The main quarries are outlined below:

Copenacre

  • Opened: Unknown
  • WW2 Purpose: Navy Store
  • Cold War: During the 50's and 60's Copenacre or Royal Navy Storage Depot (RNSD) Copenacre became "the sole place for testing, storage and issue of all electronic equipment for the navy"
  • Closed: 1995
  • Today: Part of the Hartham Park Quarry however the shaft to the quarry remains - much to the annoyance of residents !! [5]
  • Pictures/Maps:

Tunnel [Ammunition depot - largest part]

  • Opened: 1844
  • WW2 Purpose: Ammunition Store. Area was subdivided into 10 districts and were known as the Central Ammunition Depot.
  • Cold War: During the 50's and 60's Copenacre or Royal Navy Storage Depot (RNSD) Copenacre became "the sole place for testing, storage and issue of all electronic equipment for the navy"
  • Today: Part of the Tunnel quarry is today known as the Corsham Computer Centre and has a private entrance off Peel Circus.

Tunnel [South West signals centre - western end]

  • Opened: 1844
  • WW2 Purpose: Originally located in District 1 and came online in July 1943
  • Cold War: It continued in its communication focus becoming RAF Hawthorn and then part of RAF Rudloe Manor.
  • Today: Unknown - but potentially still involved with military communications

Browns

  • Opened: Unknown
  • WW2 Purpose:No.10 RAF Fighter Group responsible for air defence of the South West
  • Cold War: Used by the UKWMO until 1969 and later too became part of combined military communications.
  • Today: Unknown however access remains "restricted" and only accessible via MOD property.

Spring

  • Opened: 1840s
  • WW2 Purpose: Aircraft engine production
  • Cold War: 3 Site - the Central Government War Headquarters. The "main" bunker under Corsham but declassified in 2004
  • Today: Part (all?) used as a Data centre.

Whilst other smaller quarries exist around the Corsham area - these 4 played the largest role during World War 2 and the Cold War following.

3 Site - Central Government War Headquarters

By far the most significant area was the conversion of Spring Quarry during the 1950's to house up to 4000 central government personnel in a huge fully functioning bunker operation. This included:

  • Telephone Exchanges
  • Water Tanks
  • Supply Fans
  • Boilers
  • Laundry
  • Bakery
  • Military offices
  • Dormitories
  • Government Communications
  • Hospital
  • Carpenters
  • Welding Shop

However by the end of the Cold War it was no longer deemed essential and was run on a lower-maintenance basis. However as the threat subsided further, in 2004 it was fully declassified.

Explore a few maps and you will see plenty of "ventilation shafts" and sealed features around the Corsham area.

3 Site features today

As we can see from the images below there is much "above ground" elements from Corshams military history. What goes on underground is considered part of national security and so we don't typically get too much detail.

Note the East lift is found on Basil Hill Road on the East side:

Quarry ventilation shaft ... as it kinda says!

2 of the 3 Site lifts

The situation today

Much of the quarry estate is covered by the MOD site at Corsham. As such very limited information is known about the underground operations. However we know:

  1. ARK Data centres and Crown Data Centres operate above the former CGWHQ/ Spring Quarry (to the south of Westwells Road and on the same site as 2x lifts to the former CGWHQ) and according to a Guardian [1] article is "buried deep in the former stone mines of Corsham"
  2. Command Control Centre / Corsham Software Facility / Corsham Computers occupies the former District 9 (and possibly 8) of Tunnel Quarry and is believed to be associated with the Trident Nuclear Submarine systems. This section seems also to be referred to as Hudswell Quarry but I've not found direct reference to this.
  3. Browns Quarry - a site visit in the early 2000's revealed "rooms within what is now the PNCC were being fitted out for ongoing communication operations, and access was not possible. The layout of the areas has been retained but observations suggest that all the equipment has been removed, and at present it is an empty shell awaiting the next installation of communications equipment." [6] This maybe to do with Skynet the militaries satelite systems [12] which Babcock have been awarded and convienently sit right above the former quarry!

So it would seem that a lot of the former quarry estate is now used by the private sector but very closely related to the public.

Please note these resources are a bit of a mismatch but will hopefully give a lot more detail for research and investigations!!


  1. https://www.theguardian.com/technology/2009/nov/11/data-server-farms
  2. https://en.wikipedia.org/wiki/Central_Government_War_Headquarters
  3. http://corsham.thehumanjourney.net/pdfs/Fig20_BG_3Sfeatures.pdf
  4. https://www.heritagegateway.org.uk/Gateway/Results_Single.aspx?uid=1576682&resourceID=19191
  5. https://www.gazetteandherald.co.uk/news/24219780.will-happen-ugly-mine-shaft-left-middle-estate/
  6. http://corsham.thehumanjourney.net/pdfs/CORSHAM_report.pdf
  7. https://www.nuclearinfo.org/wp-content/uploads/2022/01/Map_Corsham_Computer_Centre_Tunnel_Quarry_Box_Hill_Tunnel_DCSA_Headquarters_Basil_Hill_Site_3_Bunker_nd_volume_1_of_1..pdf
  8. http://corsham.thehumanjourney.net/maps.htm
  9. https://www.secret-bases.co.uk/secret4.htm?permalink=corsham#corsham
  10. https://en.wikipedia.org/wiki/MOD_Corsham
  11. https://assets.publishing.service.gov.uk/media/5a7ea6cb40f0b62305b824d7/Corsham_Tunnel_version1.pdf
  12. https://www.gov.uk/government/news/400-million-contract-to-operate-military-satellite-communications-system-supports-400-uk-jobs