This post was originally published in January 2009 and was updated in August 2014.
When the Cold War was threatening Britain’s security towards the end of the 1950’s the government took the decision to build a range of nuclear bunkers. Staffed by the Royal Observer Corps they would be put to use in the event of a nuclear attack.
A total of 1563 of the monitoring posts were built, mostly to the same design as Horsham’s. They are situated at 7-8 mile intervals. In the event of a ‘four minute warning’ being issued by the Flyingdale monitoring centre in North Yorkshire the designated team of three staff would go to the site and record the size of and position of the blast. Over the next two weeks the monitoring would continue at which point it would be safe to emerge and see what remained.
The team would communicate with the regional Headquarters by telephone, latterly using the BT Tele-Talk push-to-operate control panel. However, such communication after a blast would be unlikely since the lines were overhead on wooden poles in the same way as conventional telephones. The chances of these surviving a nuclear attack would be very low.
The posts were decommissioned in the early 1990s but the bunker at Horsham remains to this day.
The bunker comprises a single vertical entrance hatch leading down into the two rooms. At the bottom of the access shaft is one very small room contained the chemical toilet. The other room contained the control centre and sleeping area. The photographs show a single bed in place but this would have been would have been two bunks when in operation. At the far end is a small hatch leading to a ventilation shaft. The hatch would have been closed during the blast but opened later when deemed safe to do so.
On the entrance hatch the base of the Ground Zero Indicator (GZI) blast monitoring equipment is still in evidence. This held a photographic film that would record the size and direction of the explosion. By comparing this with images from other posts it would be possible to triangulate the Ground Zero position. In the ceiling of the monitoring room is a channel to the surface. Through this channel a Fixed Survey Meter was operated to measure the radiation from the blast.
The control room still has some furnishings in place. A swivel chair is in front of the workstation with some shelving against the wall. All of the electrical equipment has been removed.
The post at Horsham was number 26 and was opened in December 1961 closing almost thirty years later in September 1991. It is situated in a secure area under the ownership of Horsham District Council. The exact location of the site will not be disclosed by the Horsham Photographer.
Various sundry items remain in the shelter even now. They include the original matress still in its plastic cover, government issue toilet paper, eye wash (expired Jan 1990) and Glitto cleaning powder ‘with bleach’. A large tin of Castrol Medium grease is to hand, useful for lubricating some of the heavy metal hatches. A cargo net is in place, used for lifting items in and out of the shelter. There are also some samples of photographic paper.
The Group Headquarters, opened in April 1962, was situated behind the Drill Hall in Denne Road but this was closed in 1992. It was demolished in November 2004 to make way for housing.
A modern shelter, HDC Emergency Centre, was built in 1984 and still exists under the Park North office block opposite Park House. With room for 22 people it is still fully operational with regular staff exercises, also for IT training. At the time of this update, 2014, the building is available to let.
The Horsham Photographer would like to thank ROC Remembered who arranged a visit and tour of the site. ROC Remembered have visited about 20% of the 1500 sites by the end of 2010 and intended to complete the record in the following few years. Thanks also extended to Subterranea Britannica for permission to use the shelter diagram.