The central role taken by Britain in WWII, firstly containing and then countering the expansion of the Third Reich, is duly and proudly celebrated all around the Country, with memorials and thematic exhibitions, often hosted in historical locations, regularly open for a visit.
The United Kingdom joined NATO as a founding member in 1949, and had already been at the forefront of a European anti-Soviet alliance with France since 1947. The strategic political and military ties with the US, pivotal in putting and end to WWII in Europe, were kept over the following decades, against the menace constituted by the Eastern Bloc. Thanks to its geographical position, and bolstering a nuclear arsenal, strategic bombers and submarines of its own, Britain was a major player of the Cold War.
Despite that, the Cold War left behind comparatively less memories than WWII, with only a handful installations open to the public, and somewhat out of the spotlight. In this regard, this reflects an attitude generally widespread in Europe towards the traces of the second half of the 20th century.
However, for people with an interest in the Cold War age, and more in general for those with a thing for (especially nuclear) warfare technology, there are two really unmissable sights in Northern England, which make for a vivid hands-on experience of the ‘era of Soviet threat’.
One is the Hack Green Secret Nuclear Bunker, with a fascinating history starting in WWII and spanning the entire duration of the Cold War. Here one of the finest collections of nuclear-war-related material in Europe can be found, together with much additional material from the era, in a largely preserved historical site.
Another is the York Cold War Bunker, built in the Cold War age to provide protection to the staff of the Royal Observation Corps (ROC) in case of a nuclear attack, as well as the ability to help coordinating fundamental public functions – health, transportation, food and energy supply, etc. – in a post-attack nuclear fallout scenario.
Both sites are regularly open for a visit, and provide a vivid testimony of civil and military plans and facilities seriously prepared in England for a nuclear apocalypse scenario.
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The Hack Green site is located deep in the Cheshire countryside, about one hour driving south of Manchester. Actually, it is in a really secluded location, far from any sizable urban center, and away from major roads. Even today, when this facility is working as a top-level museum, some attention to the signs is needed to reach the site.
Once by the gate, you are immediately driven back in time by the appearance of the tall military-style external fence with official government signs, and by the blunt and in impenetrable appearance of the big concrete bunker – what you see is only the part above ground level! – with a big antenna protruding from the top. Nearby, you can see an apparently still off-limits area, with a now-dead radar antenna and an old Jet Provost trainer in RAF colors.
The history of the Hack Green site dates to as back as WWII, when it was established as one of the 12 most developed Ground Controlled Intercept (GCI) centers, out of 21 total nodes in Britain. Essentially based on the airspace scanning radar plants available at the time, the so-constituted ‘Chain Home’ surveillance system was operated by the RAF, and intended to track intruding German aircraft, thus directing air force planes against them. Radar aerials appeared on site at the time, suitable against relatively slow moving propeller-driven aircraft of those years.
With the start of the Cold War, and the need to reconfigure the defense against the USSR and Warsaw Pact forces operating with jet-powered aircraft of increasing speed, several modernization plans were started in Britain, aimed at implementing more effective detection and threat-countering radar technology, like ‘Green Garlic’, and later ROTOR. The latter called for the institution of a chain of detection nodes, not much dissimilar in concept from the older ‘Chain Home’ of WWII, but much more articulated, efficient and technologically advanced. At the time one of the most expensive government-funded operations ever, 66 installations were implemented all over Britain within ROTOR before the mid 1950s, with different roles in the network. The bunker you see today on the Hack Green site was one of them.
Keeping up with the fast-developing offensive technology of the 1950s and 1960s required a continuous update of the defensive network, in particular asking for the addition of intercontinental missiles to the enemy arsenal to counter. The US-led ‘Ballistic Missile Early Warning System’ (BMEWS) included 12 early-warning radar stations around the Atlantic, including a single station in the UK (RAF Fylingdales, Yorkshire, still in operation today). Before BMEWS went operational (early 1960s), triggering a re-organization of all other defense radar systems by the time obsolete, Hack Green took an interim role as one of only 4 radar stations operated by the RAF monitoring all military and civilian traffic through the British airspace, coping with new fast jetliners. The name of the Hack Green radar site in that stage was ‘Mersey Radar North’. Finally, in 1966 the RAF released the site to the government, which put it in mothballed status.
It was in 1976 that a new life began for Hack Green. Starting in 1958, the Home Office invested much in the preparation of an emergency structure, capable of keeping of managing a post-nuclear attack scenario, and keeping the basic public functions active. In the event of a total nuclear war, a failure of the national hierarchy and military chain of command was forecast, as a result of an extensive damage to the infrastructures and communication systems. In order to recover as fast as possible in such an emergency, the UK would split in 11 regions, each with a regional seat of government (RSG). In the region, a civil Regional Commissioner would take a leading administrative role, and would be responsible for coordinating disaster recovery operations, like supplying medical resources, food, water, and reconstructing infrastructures, while waiting for the national government to reactivate its functions. The Commissioner would be aided by the UK Warning and Monitoring Organization (UKWMO), which took over the function and organization of the older Royal Observation Corps (ROC) established during WWII. This structure was further potentiated in the 1960s and 1970s, also introducing a similar regional scheme for the military in case of a nuclear attack.
The seat of the RSG was in the Regional Government Head Quarters (RGHQ). Following some years when it was hosted in Preston, then in Southport, north of Liverpool, the RGHQ for the 10th region (then 10:2, following a split in two halves of this large region) found its home in Hack Green. The former radar facility was potentiated enormously, and set up with the ability to host 160 civil and military staff for 3 months without resupply in case of a nuclear attack on the UK.
Within the framework of the emergency plan for a nuclear attack, the RGHQs all over the UK went on operating until the demise of the USSR in December 1991, to be soon deactivated over the following years. Hack Green was scrapped of all content, and put up for sale in 1993. It was privately acquired in the mid-1990s, and carefully restored in some parts, or being stocked with interesting material from the Cold War era in some of the many rooms.
A tour of the bunker
Access to the bunker is via a concrete slide, and through a metal gate. Originally the male civil servants dorm, the first room you meet is now a kind of storage for items recently incorporated in the collection. These include a jeep, a model of an Avro Shackleton, and interestingly a nuclear warhead. The original system to activate the rooftop antenna is in a cabinet along a sidewall.
The ticket office and canteen are now in the original canteen area of the Hack Green site. Restored to a 1960s appearance, parts of the kitchen furniture are original from the site. Along the sidewalls are several memorabilia items, including some original Soviet emblems, not unusual today in museums on the other side of the Iron Curtain (see for instance here), but hard to find in the UK.
An adjoining room reproduces the environment where the ROC would have worked in case of a drill or real nuclear attack. Among their function was the pinpointing of nuclear explosions. The forecast and monitoring of the fallout is strongly bound to the local weather and winds. This was kept under surveillance through reporting stations scattered on the UK territory (more than 1 thousand), which transmitted information to Hack Green and other RGHQ and UKWMO bunkers (see the York bunker later in this post). They could then coordinate recovery operations, avoiding extreme exposure to radiation of the emergency staff.
Monitoring was through dedicated sensors, and communication through specific transmission gear. Two display cases in the same room feature interesting instruments, training documents, and memorabilia items from the rich history of the ROC, documenting also their activities in WWII.
The Hack Green bunker largely retains its original arrangement. It is composed of a ground and an underground floor. Along the main corridors are interesting examples of the papers produced by the UKWMO, and by the civil defense service during the Cold War. Among them, are leaflets for the population, with best practices in case of a nuclear attack.
Also interesting are more technical posters from the era, either outlining the role of the public organizations monitoring a potential nuclear apocalypse scenario, or providing technical details on the effects of nuclear weapons – what to expect in terms of damage or health issues, depending on the type and local condition of a nuclear explosion.
For sure a focal point in the exhibition of Hack Green today is the display of nuclear warheads, and nuclear-related material. Hosted in a room previously employed by emergency staff, the exhibition retraces with original material, mock-ups, rare pictures and videos, the history of the British nuclear arsenal, managed by the Atomic Weapons Establishment (AWE).
The WE177 was designed to constitute the backbone of the air-dropped nuclear deterrent of the UK. Examples of this bomb are on display together with technical material employed to monitor their status and manage launch or drills. In service between the 1960s and the 1990s in association with larger strategic bombers like the Vulcan, or smaller fighter-bombers like some versions of the Harrier or Jaguar, it could be assembled in some different versions, sharing the same baseline construction, but with nominal yields ranging between 10 to 450 kilotons.
Also on display are pictures and mock-ups of the old Polaris warhead, together with the original casing employed to transport this 200 kilotons item! A US design, the Polaris was acquired by the UK in 1963, to supply the Royal Navy and constitute the UK underwater deterrent. The Polaris missile featured a three-warheads fuse, bearing a total yield of 600 kilotons.
A very rare artifact is the warhead of project Chevaline, a British design to improve the potential of the Polaris, which saw limited service with the Royal Navy in the 1980s. The Polaris/Chevaline was replaced by the Trident missile system, still employed today in the nuclear deterrent role.
Besides the central exhibition of nuclear warheads, the display cases in the same room offer a wealth of super-interesting technical gear and memorabilia related to nuclear weapons. These include components and cabinets of radio and radar systems, to be transported on board aircraft or to be employed on the ground. These parts come from different ages, and from several Countries, including the Eastern Bloc – for instance, a very rare Soviet suit to work on high-power radar antennas for maintenance. Powerful radars actually emit rays with a high power-over-volume (power density) ratio especially in the vicinity of the emitting apparatus. This may even turn deadly for humans (roughly like being in a microwave oven would be!), and precautions are needed when working in such environment.
A really unique collection on display is related to Geiger counters and dosimeters. These include environmental and personal use devices, from various ages and nationality.
Two display cases are dedicated to material coming from beyond the Iron Curtain, most notably from the USSR and the GDR! It is really hard to imagine how this material could manage to come to Hack Green.
Part of the display is dedicated to the civil defense corps of different Countries, with helmets, emblems, papers and uniforms, showing how similar actions in preparations for a nuclear war were carried out in many Nations of continental Europe, also in the Eastern Bloc. Actually, a very close relative of the UKWMO RGHQ control center, with a totally similar function, can be found in a perfectly preserved condition in Poland (see this post).
More memorabilia items come from the history of civil defense in the UK. Among the most rare artifacts are the only surviving example of the ‘Queen’s telephone’, which was employed for enforcing the Emergency Power Act, which among other things may have transferred power to the Regional Commissioner. There used to be one such phone in each of the RGHQ, but all were destroyed for security reasons following the shut-off of the bunkers, except this one, and the one at the other end of the line – in the Royal residence.
An adjoining room hosts a reconstruction of the radar screen room from the age Hack Green was employed as a radar station managed by the RAF. All panels are lit, providing a vivid, pure Cold War experience!
To the end of the main corridor, you can reach another entrance to the bunker, which is nowadays normally shut. However, this used to be the main entrance, and close to it are the control room of the bunker and the decontamination area.
The control room is not accessible, but the large windows allow to take a glance to its original appearance. It is still employed to control electric power and air conditioning. Manned nuclear-proof bunkers are customarily pressurized, sucking contaminated air from the outside, which is carefully filtered for poisons and radioactive particles, and pumping unfiltered bunker air to the outside (see this post for another example in a Soviet bunker).
People entering after work out in the fallout-polluted environment were decontaminated through showers, and used anti-radiation suits were left in an isolated sink still on display.
Before leaving the ground floor, you can find on the ground level the female dorm for the staff of the RGHQ bunker. In the same room, an original system for communicating on the very low frequency bandwidth has been put on display. This Cold War relic could be employed to issue orders to the strategic submarine force. This very cabinet was employed by Prime Minister Thatcher for ordering the attack against the Argentinian ship General Belgrano.
A final room on this floor is the sick bay, sized for the staff of Hack Green only, but equipped to manage health issues resulting from the exposition to a nuclear attack.
Descending to the underground floor is possible via the original stairs. The first room you meet features an exhibition of original Soviet uniforms, belonging to some high-ranking officials from various branches of the Red Army. Really hard to see in this part of the world, their origin is well documented.
Close by, is a small display of military material from the Soviet bloc, ranging from original weapons, to communication systems, emblems and instructional posters for the troops (similar to what you can find in dedicated museums in former Warsaw Pact Countries, like here or here).
Nearby is a communication room originally employed by the military staff of the bunker, working in parallel with civil servants in the management of the nuclear emergency. Original radio transmission gear of military standard is still in place.
Before entering the core preserved area of the bunker, i.e. the rooms of the RGHQ, you can find the original water and air supply systems, and the corresponding technical cabinets, in a big room on the underground level.
The rooms of the RGHQ are all interconnected, and located to the side of the corridor on the underground floor. The way they look is from the days of activity of Hack Green as a RGHQ, i.e. the 1980s. Typical Cold War technology from the time is featured in this area.
Firstly, you enter the warning room, which used to be the contact point of the RGHQ with the national surveillance system. By design, the BMEWS at Fylingdales should have picked up an incoming ICBM within 30 seconds from launch, spreading an alert signal at all levels. This would have been received here and by the entire civil defense system within 90 seconds. This would leave roughly 4 minutes (out of a total of around 6 minutes for the missile to come to Britain from the Eastern Bloc) to tell the population of the incoming missile, which would happen through some thousands sirens scattered around the UK. The physical alarm signal management system was called HANDEL, and was employed from the 1960s to 1992. The apparatus on display at Hack Green, a node of HANDEL, is notably still working, albeit disconnected.
The warning room can be accessed directly from the Commissioner’s room, both an office and private room. Original maps and furniture can be found in this room, the only private one in the bunker. Immediately next to it is the cipher office, a communication office connecting – at least in non-emergency conditions – the center with the external world. Ciphered language was employed for safe communication with governmental offices, both domestic and abroad.
Next are a conference room, for meeting within the staff of the RGHQ, and a broadcast studio. The latter was focused on radio broadcast instead of TV, since the latter would not work in case of a nuclear attack. The idea was for the Commissioner to communicate directly with the administrative region, possibly repeating messages of national significance, or instructing about local disaster recovery actions, evacuation operations, etc.
The tour goes on with a very interesting area, stuffed with original electronic and communication material. Communication from the bunker to the other similar bunkers withing the UKWMO was possible through a dedicated system called Emergency Communication Network (ECN). The main function was that of constantly updating the map of the fallout and of the operations taking place at all levels, including all surviving infrastructures. Many maps and teletypewriters, original components of the system, are part of the display.
The ‘brain’ of the system was the Message Switch Exchange (MSX). A top-tier system elaborated by British Telecom in the 1980s, it looks exceptionally complex. The lit cabinets and modules provide a really vivid impression of how it should have looked like back in the Cold War years. The electronic cabinets and wiring driving to the rooftop antenna are still lit as well.
A rare, incredible portable satellite communication antenna is on display. This was employed in peacetime condition, and stored inside the bunker when under attack.
The screens where the meteorologists and nuclear scientists displayed all the information gathered and prepared forecasts are another unusual Cold War sight.
Perhaps unexpectedly in a 1980s hi-tech environment, a purely analog, wired telephone exchange system is on display. This is original as well, and was kept in service as a ‘last line’ backup system within the ECN until 1992, should the futuristic MSX system fail under an attack.
A complement to the exhibition of the RGHQ is the fire control room, where a big screen and several communication consoles were employed for directing firefighting actions at a regional level. Following the experience of Nagasaki and the extensive nuclear tests of the 1950s, it is known that fires resulting from the extreme temperature and radiation intensity associated with a nuclear explosion are possibly even more dangerous to buildings and infrastructures than the shock-wave itself.
A display which is not original from Hack Green, but found an ideal home in this bunker, is made of a reconstructed room from the Regional Air Operation Center (UKRAOC), which would gather information from the BMEWS. The material on display used to be at RAF High Wycombe, where the UKRAOC facility was located in the Cold War years.
Fed by the BMEWS early warning station at Fylingdales, the apparatus in this room was constantly updated on the defense situation. A Soviet ICBM attack would be detected here, and from here the alarm signal to the entire national civil and military defense system would be triggered. This really one-of-a-kind reconstruction is really evoking, with the original panels all lit, and a dim light background!
A final room on the underground floor hosts a reconstruction of a Soviet missile launch room. Perhaps not accurate as a reconstruction, it is however centered on original material and memorabilia items from the Soviet bloc. This area has been employed as a set for movies.
At the base of a second stair well ascending to the ground floor you can find a reconstruction of one of the more than 1 thousand peripheral posts of the ROC. Such posts, scattered on the UK territory, gathered information for the RGHQ, and constituted the ‘sensors’ of the nuclear attack detection network. The technical gear includes over-pressure and radiation intensity transducers.
Getting there and visiting
The bunker is in a very secluded location, about 25 miles west of Stoke-on-Trent, and roughly 60 miles from Liverpool and Manchester. Very little advertised in the area, and not much known to the general public even in the UK, this hidden gem can be reached very conveniently by car, not much conveniently with public transport. The exact address is French Ln, Nantwich CW5 8BL, United Kingdom.
The bunker was built far from the crowds. Do not be worried as you see the road getting narrower and you feel like your NAV is taking you to nowhere – you are probably on the right path! Once there, you will find a large inside parking, and a top-level management of the entire facility.
Visiting is on a self-guided basis, with tons of explanatory panels and illustrations allowing to make the most out of your visit even if you have just a normal interest and preliminary knowledge of the topic. For a specialist, this super-interesting, one-of-a-kind site may require at least 2 hours for capturing the details, and possibly take pictures. Website with visiting information here.
Besides the impressive Minster and the beautiful historic town, York has the distinction of being the seat of one of the few Cold War bunkers preserved in the UK. Differently from Hack Green (see above), the bunker in York was installed relatively late in 1961, in the middle of the Cold War. Since then and until the collapse of the USSR, it acted as a node in the UK Warning and Monitoring Organization (UKWMO), collecting information and coordinating emergency actions around York in the event of a nuclear attack. A cluster of reporting points was linked to the bunker in York, which took the name of Headquarters of the N.20 Group within the UKWMO.
An eminently intelligence collection and information relay facility, the bunker was manned by the Royal Observation Corps (ROC), who provided voluntary civilian staff to support the monitoring and communication functions of the bunker in the UKWMO network. The bunker ceased operations and was basically sealed in 1991. Until that time, the ROC ran the facility, carrying out regularly scheduled drills and simulations. The bunker was designed and sized to offer its staff a self-support ability of a few weeks in a nuclear fallout scenario. Besides all supporting facilities, including water tanks, pumps and power generators, the facility was centered on a set of sensors for nuclear blast detection, as well as provision for fallout forecast and monitoring.
The bunker has been taken over by the English Heritage, a structured nationwide historical conservation association, which restored the site and opened it to the public.
The York Cold War Bunker is not far from the historical center, yet in a quiet residential area. Access is from a small parking area among low-rise buildings. The greenish paint of the concrete walls and the tall metal antenna on top cannot be spotted from much farther away than the parking itself. Curiously, the pedestrian door of the bunker stands some feet above the ground, and can be reached via a concrete stairway. Then once on top and inside, you need to descend some flights of stairs to get underground.
Compared to the Hack Green bunker, the York group headquarter is more cramped, with smaller rooms, lower ceilings and narrower corridors.
The first part of the visit covers the supporting facilities. These include a ventilation system, which as customary for nuclear-proof bunkers (but the same is true for older bunkers dating from WWII) filtered the incoming air and ejected the inside air, basically pressurizing the bunker environment with respect to the outside atmospheric pressure. This avoided passive ingestion of contaminated air from the outside.
A power generator and a water pumping system are also visible. A control panel for all the plants has been preserved, similar to the machinery in this area, dating from the time of construction.
The centerpiece of the visit is of course the reporting room. The reason for putting a headquarters in relatively low-sized York was the presence in the area of significant food production industries, as well as of a major railway node in Northern England. Furthermore, military facilities like the only BMEWS station in the UK happened to be in Fylingdales, northern Yorkshire. These features would make York a valuable strategic target for an attacking enemy. The main function of the bunker within the UKWMO was that of ascertaining the position and intensity of a nuclear explosion on the territory covered by its jurisdiction.
Anticipated by the early warning ballistic missile detection system protecting the UK, the hit could be recorded by the sensors available in the bunker or in other reporting points scattered around in the country. The bunker would then try to predict and follow the evolution of the fallout. This would allow coordinating emergency and recovery actions including fire suppression, medical evacuation, water and food transport and supply, etc.
The central reporting room looks mostly like an operations room in a military headquarter. It is structured on two levels, with large maps and boards for visually updating the situation and writing information. Batteries of telephones and teletypewriters allowed obtaining communications and sending updated information to allow emergency services as well as decision centers to carry out post-attack operations. This system was not dissimilar from the counterpart beyond the Iron Curtain (see for instance this center in Poland).
Nearby the reporting room, the components of the sensor suite allowing to detect the position and intensity of a nuclear explosion are on display.
The first is the bomb-power indicator (BPI). The working principle is that of reading the over-pressure caused by the shock-wave invariably produced by an explosion, and particularly intense for a nuclear explosion, releasing an immense amount of energy in a small volume and within a very short time. The supersonic traveling shock-wave is responsible for the mechanical breaking of building and superstructures, like antennas, suspended power lines, bridges, piers, etc. Being a wave of pressure, its intensity can be measured by pressure transducers, which for the BPI show the reading on a simple analog dial.
The transducer, seen handing from the ceiling in the exhibition, would stand on the rooftop of the bunker, exposed to the explosion. This type of sensor was also installed in smaller reporting points scattered over the territory of the UK.
A second sensor was the ground zero indicator (GZI). Here the working principle was also very simple. The main element in the GZI is a metal drum with a small hole in the side, and a piece of photographic paper covering the inside surface of the cylinder. An explosion would send a high-energy light beam through the hole, producing an impression on a precise point on the paper. By positioning in a very accurate way the drum on its pedestal on top of the bunker, according to a precise fine-tuning, it was possible to retrieve the direction of the incoming beam. By composing the reading of more than one precisely-located drum, it was possible to pinpoint the position of the explosion by triangulation, both in terms of geographical position and altitude. The latter is a very relevant practical information, since for instance the quality and hazard of the fallout are strongly related to the proximity of the explosion to the ground.
The GZI, a purely analog sensor, had the odd feature of requiring collection of the photographic paper by venturing outside of the bunker after and explosion, i.e. facing the fallout.
The third and most evolved system on display is an AWDREY computer. The name stands for Atomic Weapon Detection Recognition and Estimation of Yield. This artifact is very rare to see, and a quite refined piece of engineering for the time. It was supplied to 12 headquarter bunkers of the UKWMO, including York, and was operative from the early 1970s. The computer is the computational part of the system, whereas the detection system was based on a sophisticated transducer put outside, on top of the bunker. The working principle was much more sophisticated here, and related to the evolution of the intensity of the radiation coming from the core of the explosions in the first instants of the detonation process. Several stages of a nuclear explosions happen in a row on a scale of a few millionths of a second. These include a predictable oscillation of the intensity of radiation. The exact features of this oscillation are correlated to the yield of the explosion. The ability of AWDREY to collect and interpret data from the early stage of the explosion would allow it to reconstruct the position and yield of the explosion at once.
Tuned on experimental data from nuclear testing in the field, this system delivered good general performance, with some inaccuracy in case of intense atmospheric phenomena taking place – or during fireworks, when the York system was apparently misled in one occasion, interpreting it as a Soviet attack!
The tour is completed with a view of the dorm for the civil servants of the ROC, and with a short exhibition on some historical and political aspects of the Cold War.
Getting there and visiting
The York Cold War Bunker is professionally managed by the English Heritage. Visiting is only possible with a guide. Please note that as of 2022, pre-booking is strictly necessary, since there is no ticket office on site. The guided tour lasts about 45 minutes, including a well-crafted introductory video. At the time of writing, only the first underground floor is open for a visit, but plans for an expansion of the visible part of the facility are being drafted.
The tour is very interesting and detailed, with some educated humor to make it more enjoyable! For specialists, it will be too quick, especially if you like to take pictures. However, the site indeed deserves a careful look also for the more technically-minded people, especially considering the little number of similar facilities open in Europe – and of course in the UK, where it is a one-of-a-kind destination, and a true must for Cold War historians.
The location is about two miles west of York Minster. Convenient to reach by car, several public parking lots are available in front of the gate or in the neighborhood. The exact address is Monument Cl, Holgate, York YO24 4HT, United Kingdom. Website with full information here.