Kelvedon Hatch nuclear bunker

A wonderful photo of boffins at work in the (level 1) Ops Room at Kelvedon Hatch circa 1962
THE UNITED KINGDOM DURING THE COLD WAR, 1945-1991 (D 106284) United Kingdom Warning and Monitoring Organisation. Metropolitan Sector Operations Centre. Operations Room – Scientists at Work. Copyright: © IWM. Original Source:

For those still following this page, my apologies for another lengthy drought. I’ve just been too busy unfortunately. However, I have been working on a few things, the first of which follows…

This spring I finally got around to visiting one of the best preserved Cold War nuclear bunkers in the UK – Kelvedon Hatch in Essex. First, given the implication of me commenting on anything historical here, let me say that I absolutely loved this place. We owe the owner and manager, Mr Parrish, a massive debt for rescuing it for the nation rather than being vandalised or destroyed entirely. That said, it is not without its issues from an historical standpoint. Parrish claimed in 1996 that “Everything is original — except the John Major figure…It is exactly as the Government left it”. The Facebook page today likewise proclaims “Everything is as it was left by the Government, when the bunker was decommissioned in the early 90’s.” This is not the case. 

Praise for the bunker is (rightly) almost universal, but at the same time it’s attracted very little scholarly attention. I did find criticism in David Lowe and Tony Joel’s ‘Remembering the Cold War: Global Contest and National Stories’ (2014, p.59) where they remark that Kelvedon Hatch’s “…testimony to the Cold War is somewhat compromised by its private ownership. The organization and upkeep of displays is very tired and occasionally misplaced (a dummy of former prime minister Margaret Thatcher, for instance, sits next to communications equipment dating from the 1960s), and the bunker jostles with youth-focused outside activities…”. Digging out Imperial War Museum and Historic England photos from 1992 and 1997 respectively, it isn’t just the interpretation that could be described as “tired”, sadly. The general condition of the place has gone from absolutely pristine to, shall we say, looking its age. Flooring and painted surfaces are worn (but not peeling), plant machinery is looking rough (albeit not visibly corroded), and there are worrying cracks in a couple of walls. I feel terrible pointing this out because if you’re going to privately run an underground three-storey office block formerly maintained at great taxpayer’s expense, maintenance is an enormous and inevitable problem. I certainly have no issue with the adjacent outdoor activities – how else are they going to fund this place? Mr Parrish’s recorded audioguide tour, whilst engaging, informative, and funny, doesn’t give the full story, but then how could it? Even Lowe and Joel blame the private status of the site rather than the owner himself. However, the whole place is in a sort of three-way limbo between an attempt at reconstructing actual wartime occupation of the final RGHQ phase, attempts to evoke its earlier days, and a sort of ad hoc Cold War history museum. It’s great for most visitors, but for those of us wanting more, I decided to try to disentangle this confusion using the available information, plans, photos, and film footage of the site’s different eras. 

Contrary to just about all of the information out there, there were actually three operational phases as follows:

Phase 1 – ROTOR bunker

1951 – 1953: Construction 

1953 – 1957: RAF ROTOR (R4 type) Metropolitan Sector Operational Control (MSOC) 

1957 – 1962: United Kingdom Warning & Monitoring Organisation (UKWMO)/Royal Observer Corps (ROC) Metropolitan Sector HQ co-located with the ‘rump’ RAF SOC following closure of the ROTOR programme.

Plans: via Historic England

Variant plans via the RAF Barnton Quarry restoration project (you can right-click and open image in a new tab to view a larger version)

Film: Kelvedon Hatch features prominently in the 1962 film ‘The Hole in the Ground’ (note this copy misses out a short introduction set outside the bungalow). By this time the RAF have handed over operations to the UKWMO, but the fabric of the building has yet to change. In the opening scene we see UKWMO team members running into the above ground guardhouse, then proceeding down the long access tunnel and into the main bunker, the blast doors slamming shut behind them. Visible in the background is some sort of equipment stowage or coat rack (!) located where the Home Office Radio Room would later be established. We then see the Chief Sector Warning Officer and his team of scientists emerge from the doorway at top left on the above-linked plan and immediately turn right, walking under the now-defunct tote board (its red-painted support posts and frame are visible). At this point we get a great view of almost the whole Ops Room. At the opposite side of the room the bottom of the now disused RAF Sector Ops glazed-in ‘cabins’ are visible (these appear more clearly later on as well). They then walk behind desks manned by (as explained in the film) Post Office telephonists who have volunteered under UKWMO. The team then turns right again, disappearing behind a large black pinboard (with two large maps on this side of it) that effectively bisects the room into admin/comms and scientific analysis. We pick up with the scientific team later as they perusing maps and charts. We get a reverse shot later on that shows the tote support structure again, in front of the group, complete with a colour-coded ‘sector’ type clock (as used in RAF ops rooms in the Second World War). Toward the end of the film we see the bottom right corner of the room with red double doors (these were visible in the distance in the establishing shot of the room). Pleasingly, these original 1950s doors are still in situ today (along with a lot of others!), repainted light green and with an additional 1985 vintage inner door in front of them. 

The whole setup is remarkably ad hoc – simple black cloth-covered pin-boards, ordinary tables with switchboard-style phones, individual message trays and pigeonholes made of unpainted wood. 

Photos: There are two known images, one of which is shown in photocopied form on the tour – the middle two rows of cabins with the top row just in shot – and the two plotting tables on Level 1 below the cabins. I was also very pleased to discover (I believe for the first time) IWM photo D 106284 showing a civilian UKWMO scientist plotting nuclear bursts on a map using a radiac slide rule. If anyone recognises the communications kit to the right of his drawing board, comment below. This shot is a perfect match for the scenes in the film.

Description: Kelvedon Hatch differed from all other R4 bunkers in having a tunnel that emerged into Level 1 rather than Level 3. Note that the cage opposite the main blast doors, today filled with random weapons as though an armoury, actually housed the 1950s electrical transformer for the site (plans are labelled as such and photos of other ROTOR bunkers still show the plant in place). Much is made of the ‘disguised’ above-ground bungalow, but this was a real, functioning military-style guardroom like any other, with toilets, offices, and an armoury (there’s a plan here that also appears in McCamley’s book). The armoury later became a decontamination room (this room’s door, behind the outer blast door, is still so labelled). All ROTOR bunkers throughout their various phases of use had a perimeter chain-link fence patrolled by armed guards and the actual radar stations were effectively military barracks with massive rotating radar dishes. The above-ground structures may have been intended to be low-profile, and certainly were at Kelvedon Hatch more so than elsewhere (since KH never had radar arrays and had the advantage of some tree cover) but were certainly not disguised. 

As a command centre for a short-lived RAF radar network, the site was focused around a central Operations Room ‘well’ three floors deep, with plotting boards at the bottom, a tall ‘tote’ mission control board at the front, and glazed, angled control ‘cabins’ wrapped around the back. The central room on Level 1 housed the two large plotting tables and the support posts for the tote. The remainder of the floor comprised two large rooms – ‘Apparatus’ at left and the main plant room at right. The two plant rooms remained much the same throughout all three phases. 

Moving up to level 2 we again find the glazed ops ‘well’ in the middle, surrounded by a corridor with office spaces either side and beyond this a maze of partition walls defining the toilet blocks (the women’s toilet being larger than the men’s) and a number of offices/rooms of varying size. By far the largest is an open plan space at top left. The plans (nor any other source) don’t reveal what the purpose of any of these might have been, unfortunately. We have a bit more information on the top floor (level 3) which again has the ops well but without the corridor around it. Instead there is a ring of self-contained offices. At left we have two large unidentified rooms with a thin partition wall and on the other side of a more substantial wall running from the stairwell to the bottom wall, a row of squarish offices with a corridor running past them. At right we have some labels, denoting the Women’s Royal Air Force (WRAF) rest room 

Phase 2 – Sub-Regional Headquarters/Sub-Regional Control

1963 – 1966: SRHQ for Region 4, ‘East’

1966 – 1985: S-RC 4.2 (Region 4, Control 2)

NB UKWMO/ROC Sector HQ retained until 1971 only

Plans: displayed (until they eventually fall apart) in the access tunnel, via Alamy stock images. Undated but believed to be ca.1965. Sadly I didn’t take my own photo so a lot of the room numbers and labels are not legible on the image we have. 

Photos/Film: None, however see ‘The Hole in the Ground’ above – the room may have changed a lot ca.1965 but the operations carried out, the kit, and the personnel involved would have been much the same.


The first phase intended for ‘continuity of government’ in the event of a Third World War. The most significant change for this phase was that the ROTOR Operations ‘well’ was floored over. Rooms were also reconfigured throughout in keeping with the bunker’s new role. The men’s lavatory was expanded and a corridor created along the back of the toilets with partitioned offices along it (those labelled with a purpose are ‘Tape Room’ and ‘PBX’, a type of telephone exchange). New rooms were built on the left side of the floor telephone exchange Offices on Level 2 were knocked through to create a large Conference Room. Others were more significant. Notably, sleeping accommodation was installed; one dedicated 20 bunk dormitory on Level 3 and another 20 or so bunk beds in other areas, including a full row of beds along the access tunnel (so accommodation for around 80 people). Next door to the dorm was an equivalently sized room labelled ‘DEPTS’; the first dedicated working space for representatives of different government departments. The former RAF and WRAF rest rooms were converted into a single large unisex ‘Canteen Rest Room’ with adjoining kitchen capable of providing hot meals. The centre of Level 1 (rooms 101 and 103) remained in use as ‘Sector’ (presumably an operations room), but around 1/3rd of the room (101) was walled off as a sleeping area with bunks along the back wall. Another four small rooms on Level 2 were also designated ‘Sector’, with other rooms allocated to ‘Military’ and ‘Fire’ (one large room), Scientists, and Civil Defence Operations. The BBC studio was installed in its current location (albeit a different configuration) next to the GPO (General Post Office) ‘frame room’. The plant rooms (the main room being 102) remained unchanged. All told, Level 1 was already close to its Phase 3 incarnation in terms of usage and layout, if not in detail, but 2 and 3 remained quite different.

Phase 3 – RGHQ

1985 – 1992: Regional Government Headquarters, Metropolitan Region (RGHQ 5.1)

Plans: Only Level 1 has been reproduced online. To see this final layout (albeit in Phase 4 ‘trim’) you can also check out various tours on YouTube (including this short official one), and the complete plans were published in Judy Cowan’s 1994 pamphlet ‘Kelvedon Hatch Secret Bunker’. Better yet, visit the bunker yourself if you can; this article is primarily intended for people like me who visited but didn’t get a full picture of the site.

Photos: A whole series of Imperial War Museum record shots taken on decommissioning in 1992. These show how very sparse the place was, contrary to modern claims that the site is as the government left it. All we see are tables, chairs and telephones. 


Internal walls were again rebuilt, this time in handily identifiable blockwork construction. Basically, if you see breeze-blocks, you’re looking at a 1980s alteration. The entrance to the access tunnel was redesigned to incorporate a new generator room into the near end of the tunnel (the exhaust stacks for the diesel engines are still visible to the left of the bungalow and have changed in design since the 1962 film). The complete row of bunks was replaced by a few fold-down bed frames attached to the wall (presumably for a guardroom ‘watch’, since there was now space for everyone on Level 3). The area at the far end of the access tunnel was enlarged and fitted with sliding blast doors on tracks to create a ‘Home Office Radio Room’. New generator cabinets and a siren point were installed just inside the main blast doors (it’s not clear whether the transformer outside them remained in place). The UKWMO Sector HQ relocated to the newly expanded Group HQ building at Horsham, and ‘Sector’ became office/operational space for “Uniformed Services” (outfitted with tables, chairs, lockers and desk phones), but the Communications Centre or COMCEN (also on Level 1) remained part of the wider Emergency Communication Network (CEN) with access to UKWMO/ROC data. The entrance used by the team three years earlier in ‘The Hole in the Ground’ and the door opposite it were walled off to create a corridor bypassing the new smaller main room (visitors now enter the room in the middle through a door marked ‘no entry’) and a small admin room (now one of several small cinemas for visitors). The science team were moved from Level 2 down to Level 1 next to a much smaller BBC studio. On Level 2 the formerly closed-in offices across the middle third of the room were knocked through to create one large central open-plan office. Note that the various wooden painted signs around the walls in this room are not original, as shown by the 1992 photos of the space and, in the 1997 shots, their initial suspension from the walls on string loops. Later they were (regrettably) screwed into the walls. These seem too specific in terms of content and style to be made up, but if they came from another site I don’t know which one or what era. 

Closed offices remained around the perimeter of the floor but were also reconfigured. Where there had been only one office/bedroom for a government official, a new corridor (down which the modern tour proceeds) accommodated three such spaces; 203 for the Regional Commissioner, 204 for the Principal Officer, and 205 for the Prime Minister (although it’s far from clear that the PM would ever have used this room). The row of offices that visitors see when they emerge from said corridor are wholly new for this phase – their predecessors having been ripped out. The first office at left is the ‘Secretariat’ (206), with a small room within this (207) housing a typing pool (previously located on Level 3). The adjoining rooms (208 and 209) were a truncated version of the Conference Room and, in the corner (now an event room) the Information Room.

Up on Level 3 the existing dormitory space was doubled, taking up the former government department space (there now being much more space for them on Level 2). This was divided by sex, men in the right hand room (302 – now an off-limits meetings/event space) with a small room next door for ‘Drivers’ (likely now a store for the giftshop), and women in the two rooms next door (301 and 308). Another two (also adjoining) male dorm rooms (309 and 311) were established on the other side of the toilets and Sick Bay (310 – seen here before stripping out and dummying-up). This area is partly correct today but 309 is, with some artistic licence, dressed as an emergency operating theatre. In reality this room would be fitted out with bunks and lockers in anticipation of use. We know this because we have a photo taken from 309 looking into 311. As cramped as the recreated dorms in the bunker are today, they are nothing compared to the reality, and the beds and lockers there today are not the same as they originally were.

Phase 4 – Visitor Attraction

1994: Sold back to the landowning family.

1995 – Present: Opened to the public.

Plans: represented by the fire evacuation map located in the bunker. Identical to Phase 3 but with two additions – a new metal staircase in the upper right corner of Level 2 allowing access from the open plan office straight up to the room outside the canteen on Level 3 (marked ‘Common Room’ on the Phase 3 plan). Although not included on the 1985 plan, it is clearly original to the RGHQ phase. The other change is the exit tunnel sadly bored through the wall of the Common Room to comply with fire regulations.

Photos: Another series from Historic England who documented the site as a new visitor attraction in 1997, by which time a lot of the present embellishments had been made but without the additional clutter and the ravages of time that we see today.

Description: As part of the decommissioning process, all of the original furniture and communications equipment (other than some of the telephone exchange) was removed. The original 1950s transformer room was also stripped out, but the rest of the plant remained. By 1997 the bunker was increasingly ‘dressed’ with surplus Cold War-era furniture, equipment, artefacts (most of the phones are marked up with the station crest of RAF St Athan) and some basic museum-style diorama displays ranging from individual dummies in wigs to an attempt at a ‘Threads’-style post-apocalypse household. A recent addition is a large-scale Spitfire model that has for some reason been suspended over the plotting table in the former Operations Room. 

Note that some of the room door labels (which slide into universal holders affixed to the doors – the actual room numbers are permanent) seem to have been moved over the years. The label for room 202, ‘Government Departments’ is currently fitted to the door for room 201, which per the plans should be ‘Common Services’ (and is loosely interpreted as such today with racks of stationery). Male and female dorm rooms 302 and 301 have had their labels swapped for some reason.


What you see at Kelvedon Hatch bunker today is therefore mostly a very…busy take on the final operational (RGHQ) phase. I will say again; this is an incredible place, it just needs some analysis to make full sense of. The current attraction conveys the general sense of what all three phases were about, it’s just not clear how these fit within chronology and the fabric of the building itself. If it were up to me (clearly it isn’t) I would thin out the accumulated clutter and remove all of the shop dummy diorama displays. Remember – none of the furniture or props there now are original to the site. I’d choose to depict Phase 3 throughout, and choose one room to clearly demarcate and curate as a museum to interpret the first two Phases, with an introductory display on Civil Defence.  


The bunker is mentioned in a number of published works and websites, nearly all of them are superficial in their treatment of the site or outright wrong. I recommend:

Clarke, Bob. 2005. ‘Four Minute Warning: Britain’s Cold War’. The History Press.

Cowan, Judy. 1994. ‘The Kelvedon Hatch Secret Bunker’. 

McCamley, Nick, 2002. ‘Cold War Secret Nuclear Bunkers: The Passive Defence of the Western World During the Cold War’. Pen & Sword.