History – In brief

After the end of WWII and the collapse of the Third Reich, the territory now belonging to the Czech Republic fell on the Soviet side of the Iron Curtain. Together with today’s Slovakia, it formed the now disappeared unitary state of Czechoslovakia. Despite laying right on the border with the West – including Bavaria, which was part of West Germany and NATO – communist Czechoslovakia enjoyed a relative autonomy from the USSR, until the announced liberally-oriented reforms of the local communist leader Dubcek in the spring of 1968 triggered a violent reaction by the Soviet leader of the time, Leonid Brezhnev (see here). About 250’000 troops from the Warsaw Pact, including the USSR, landed in the Country. As a result, the Soviets established a more hardcore and USSR-compliant local communist regime, and largely increased their military presence.

Similar to the German Democratic Republic (see here for instance), Hungary (see here) or Poland (see here), since then also in Czechoslovakia the local national Army was flanked by a significant contingent of Soviet troops, who left only after the entire Soviet-fueled communist empire started to crumble, at the beginning of the 1990s.

Consequently, for the last two decades of the Cold War, Czechoslovakia was a highly militarized country similar to other ones in the Warsaw Pact (see here). Its geographical position on the border with the West meant it received supply for a high-technology anti-aircraft barrier (see here). Two major airbases in Czechoslovakia were taken over for use by the Soviets and strongly potentiated (see here).

Soviet Nuclear Depots in Czechoslovakia

Beside conventional forces, also nuclear warheads were part of the arsenal deployed in this Country. Where in the late 1960s Soviet strategic nuclear forces were already mostly based on submarine-launched missiles and ICBMs ground-launched from within the USSR’s borders, tactical forces were forward-deployed to satellite countries, to be readily operative in case of war in Europe. Missile systems like the SCUD, Luna (NATO: Frog) and Tochka (NATO: Scarab) were deployed to the Warsaw Pact, supplying either the local Armies or the Soviet forces on site. Typically armed with conventional warheads, these systems were compatible with nuclear warheads too, making them more versatile, and of great use in case of a war against NATO forces in central and western Europe (see here).

Irrespective of their employment by a local national Army or a Soviet missile force, nuclear warheads were kept separated from the rest of the missile system for security, and invariably under strict and exclusive Soviet control. Bunker sites were purpose built in all components of the Warsaw Pact for storing nuclear warheads – see page 46 of this CIA document, showing with some accuracy the location of the corresponding bases.

Granit– and Basalt-type bunkers were typically prepared on airfields or artillery bases, for short-term storage of soon-to-be-launched nuclear weapons. Instead, top-security Monolith-type bunkers (the triangles on the map in the CIA document) were intended for long-term storage of nuclear ordnance.

Monolith-type bunkers were built by local companies on a standard design in the Soviet military inventory, and were implemented in satellite Countries in the late 1960s. Czechoslovakia received three such sites, which took the names Javor 50, by the town of Bílina, Javor 51, close to Míšov, and Javor 52, close to the town of Bělá pod Bezdězem. All three locations are in the north-western regions of today’s Czech Republic.

The Soviet military started withdrawing the nuclear warheads from satellite Countries in 1989, months before the collapse of the wall in Berlin. As for Czechoslovakia, by 1990 all nuclear forces had been moved back to the USSR. Following the end of the Cold War, Monolith-bunkers – similar to most of the colossal inventory of forward-deployed military installations formerly set up by the Soviet Union – were declared surplus by the Countries where they had been implemented.

These primary relics of the Cold War have known since then different destinies. Some of them have been hastily demolished, and together with their associated fragments of recent history, they have almost completely disappeared into oblivion. Luckily, a few are currently still in private hands, and still in existence (see here and here) – specimens of recent military technology, and a vivid memento from recent history, when the map of Europe looked very different from now. Two can be visited, of which one is Javor 51, in the Czech Republic, the main topic of this post. This has been turned into the ‘Atom Museum’, which has the distinction of being the only Monolith-type site in the world offering visits on a regular schedule (the other open site is Podborsko, in Poland, covered here, which is open by appointment).

Also displayed in the following are some pictures of the now inaccessible site Javor 52 in former Czechoslovakia. Photographs were taken in 2020 (Javor 52) and 2022 (Javor 51).

Sights

Javor 51 – The Atom Museum, Míšov

An exceptionally well preserved and high-profile witness of the Cold War, the nuclear depot Javor 51 is a good example of a Monolith-type installation. These bases were centered around two identical semi-interred bunkers for nuclear warheads.

When starting a visit, you will soon make your way to the unloading platform of bunker Nr.1. The shape of the metal canopy, and the small control booth with glass windows overlooking the platform are pretty unique to this site. The metal wall fencing the unloading area is still in its camo coat outside, and greenish paint inside. Caution writings in Russian are still clearly visible. Concrete slabs clearly bear the date of manufacture – 1968. This site was reportedly activated on the 26th of December, 1968.

Even the lamps look original. Some of the – likely – tons of material left by the Soviets on the premises of this site has been put on display ahead of the massive bunker door.

The opening mechanism of the latter is a nice work of mechanics. Four plugs actually lock or unlock the door. They can be moved by means of a manual crank, or likely in the past via an electric mechanism (some wiring is still visible). The thickness of the doors is really impressive (look for the cap of my wide lens on the ground in a picture below for comparison!).

Each bunker had two ground-level entrances to the opposite ends, each with two blast-proof doors in a sequence. Warheads were transported by truck, unloaded beside the entrance of one of the two bunkers, and carried inside through the two doors, which constituted an air-tight airlock.

Today, you can see the inside main hall of the bunkers from the outside during a visit. This was likely not the case in the days of operation. The opening procedure required a request signal to travel all the way to Moscow, and a trigger signal traveling in the opposite direction. Once past the first (external) door with the warhead trolley, that door was shut, and the procedure was repeated for the second door, giving access to the inside of the bunker.

A security trigger told Moscow when the door was open. It can still be seen hanging from top of the door frame.

Once inside, you find yourself on a suspended concrete platform. The warhead trolley had to be lowered via a crane – still in place – to the bottom of the cellar ahead, i.e. to the underground level. The stairs now greatly facilitating visitor’s motion around the bunker were not in place back then, and descending to the underground level for the technicians was via a hatch in the floor of the suspended platform, and a ladder close to the side wall.

On the platform, an original Soviet-made air conditioning system can be seen – with original labeling – and signs in Russian are on display on the walls.

The platform is also a vantage point to see the extensive array of heat-exchangers put along a sidewall of the central hall – atmosphere control was of primary importance for the relatively delicate nuclear warheads. Each of them traveled and was kept in a pressurized canister. However, also the storage site was under careful atmospheric control.

To the opposite end of the bunker, the inner tight door of the second entrance can be clearly seen, ahead of another suspended platform. The warheads left the bunker for maintenance (they might have left also for use, but this never happened, except possibly on drills) from that entrance, which had a loading platform outside for putting the warheads on trucks (this can be better seen in other Monolith sites, like Urkut in Hungary, or Stolzenhain in Germany).

Down on the lower level, the main bunker hall gives access to one side to four big cellars, where the warheads spent their time in storage, and to the other sides to technical rooms. The pavement in the storage cellars features the original metal strongpoints, used to anchor the trolleys for the warheads to the ground. This was in case of a shockwave investing the site in an attack, to avoid the trolleys moving and crashing against one another. The original hooks with spherical joints to link the trolley to the strongpoints are also on display.

The storage cellars today have been used to display informative panels, with many interesting pictures and schemes. These include some from major sites connected with the history of nuclear weaponry in the Soviet Union (like from the test site of Semipalatinsk) and the US (like the Titan Museum near Tucson, AZ, covered in this post).

A few former technical rooms are used to store much original technical gear. This ranges from spare parts, tools and personal gear like working suits left by the Soviets (most with signs in Russian), to items ‘Made in Czechoslovakia’ or even radiation detectors from Britain and the West, gathered here for display and comparison.

Some of these spare parts are wrapped and sealed in Russian, looking like they were cataloged back in the time of operations.

In the main hall, many rare vintage pictures retrace the presence of Soviet military forces on this site as well as others in Czechoslovakia. Magnified copies of rare pictures portray the trucks, canisters and the very warheads likely involved in transport and storage in Javor 51. Actually, much mystery exists around the deployment of nuclear ordnance by the USSR outside its borders (not only to Czechoslovakia). Historical and technical information today made available, even to a dedicated public, is very limited, making this chapter of Cold War history even more intriguing.

Again in the central hall, cabinets for monitoring the nuclear warheads can be seen hanging from the walls, painted in blue. Each warhead used to be stored in a canister, which was periodically linked to these cabinets to check the inner atmosphere, temperature, etc., in order to monitor the health of its very sensitive content.

A large part of the technical/living rooms has been preserved in its original appearance. You can see parts of an air conditioning system, a big water tank, a toilet, a now empty bedroom for the troops. The bunker was constantly manned inside by typically six people, who operated in shifts. They did not sleep there, nor used the toilet much due to poor drainage. However, these facilities were used in drills, and were intended for the case of real war operations, when the bunker might have been sealed from the outside.

The electric cabinets take a dedicated room, like the huge air filters and pumps (Soviet made), installed to grant survival of the people inside the bunker in case of an attack with nuclear weapons or other special warfare. Clearly, the level of safety in the design of the bunker stemmed from the fact that it was considered by the Soviet as a a strategic target for NATO forces.

The last technical rooms host a big Diesel generator, supplied with air from the outside, and a big fuel tank in an adjoining room. Many labels bear writings in Russian, but the generator appears to be made in Czechoslovakia. The bunker was linked to the usual electric power grid of the region, and the generator was intended for emergency operations, in case the grid was lost or the bunker was isolated.

From the technical area, it was possible to access or exit the bunker, via a human-size airlock. The innermost tight door can be seen painted in yellow, with a locking mechanism resembling that of the major tight doors for the missile warheads. Outside the airlock, climbing three levels of ladders was required to get to the surface. This was the normal access to the bunker for the military technical staff, except when warheads arrived or left the storage (this was made via the major entrances, as explained).

Back outside, the second bunker, Nr.2, can be found at a short distance from the former. Nr.2 is being prepared for an exhibition on technology. At the time of writing, it can be toured except for the technical/living rooms. It is in a very good condition, and allows to get similar details as the previous Nr.1 on the construction of this type of facility – including the heating/air conditioning system.

The blue cabinets for plugging the canister for routine status checking and maintenance can be found also in Nr.2 in good shape.

Clearly visible here are the doors closing the technical areas and the warhead cellars. The latter were monitored for security just like the external airtight doors of the bunker, each with a sensor telling controllers whether the cellar was locked or not.

The airlock is covered in soot, possibly the result of a fire. Ahead of the entrance, the unloading platform is very interesting, having a unique set of light doors which had to be opened to allow trucks to come in. The concrete part of the platform appears slightly off-standard, with a short lateral concrete ramp, giving access to the main platform from one side. Parts of missiles – original – are being gathered in this area for display.

Monolith sites include two bunkers, which are the core of a strongly defended fenced area. In Javor 51, fences except the external one have been removed for the safety of visitors (rusty barbed wire can be very dangerous). These can still be found in other similar installations (see here). Similarly, the troops and technicians working on site lived in purpose-built housing, segregated from local communities. In Javor 51, this housing still exists, but cannot be visited.