WARNING The parts of the site described below are dangerous. The underground site was abandoned 40 years ago and is decaying in parts. One intruder has already died during an unauthorised entry and others have been hurt. All items of value were removed prior to its sale in 1965 and all that remains underground is the shell.
Entry to the new, underground installation was through a guardhouse built to look like a bungalow.Examples of similar bunkers are seen at many locations round the country and a particularly fine example is open to the public at Kelvedon Hatch. Similar features are seen at many of the sites described in the Research Study Group web site.
The bungalow viewed from the north. The Truleigh Hill bungalow was completed in 1952, shortly after the death of the King. Even while it was being built equipment was being lowered into the tunnel by crane then taken along the tunnel to the bunker for installation. Once completed, the only access to the tunnel was through the front door and the guardroom or through the steel plant access doors at the rear. The main gate for the whole site was on the road at the left-hand edge of this photograph.
Kelvedon Hatch was built in about 1953 as a Sector Operations Centre and is a three-level R4 bunker, much larger than Truleigh Hill. Even so, the typical guardroom bungalow can be seen marking the entrance to what is now cold war museum open to the public.
The bungalow was actually a reinforced building capable of withstanding significant blast effects. The normal entrance would have been through the front door and into the guardroom but there were also alternative access points at the rear. Some idea of the original degree of protection may be had by examining the windows. The brickwork is backed by concrete and steel shutters which remain from the original use. The ceiling of the ground floor is a reinforce 
concrete slab which supported the water supply storage tanks for the installation. Water was supplied from the northern side of the hill by two pumps at Hortons Corner. When the levels in the bungalow tanks fell, the pumps would cut in automatically and force water up the hill through a pipeline with two non-return valves. The supply had two separate feeds so that the load could be spread – the pumps were quite capable of drawing enough water to deplete supplies to a significant area of housing otherwise. The excavation for the bunker was done by a single digger which gradually dug itself into the ground and created a hole some 60 feet deep. The spoil was removed by a fleet of trucks many of which, the drivers were paid by the load, actually drove down the steep northern side of the hill rather than go the long way through Shoreham. rather aptly, a number of the dangerous driving scenes from the 1957 film ‘Hell Drivers’ (Stanley Baker, Patrick MacGoohan, Herbert Lom, Sid James etc) were filmed along the roadway from Truleigh Hill to the corner on top of Beeding Hill.
At the back of the bungalow can be seen the larger doors used when equipment, rather than people, had to gain access. The picture shows the main equipment access doors which are approximately 9 feet high and 6 feet wide. These steel doors lead to the same staircase as the front door but are wide enough to allow for plant equipment to be brought in. The shutter on the wall to the right covers another access port which is protected by a sliding steel door on the inside. All access to the staircase is now sealed off except via these steel doors.
