The Wollenberg Bunker – Linking East Germany and the USSR

Heading to Berlin or the former GDR? Looking for traces of the Cold War open for a visit?

A Travel Guide to COLD WAR SITES in EAST GERMANY

Second Edition - 2024

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The events taking place on the geopolitical stage during the last decade of the Cold War – the 1980s – gave little indication of the imminent collapse of the Soviet-led Eastern Bloc (1989-1991). Correspondingly, looking at the amount of technology developed and deployed in the military field during the late, hi-tech stage of the Cold War, it is easy to notice that opponents on both sides of the Iron Curtain dedicated a significant (and even increasing) budget in preparation for a possible total confrontation. Reading papers and specialized books from the time, the outbreak of an open conflict, such to put a violent and abrupt end to years of opposition between the two opposing systems by recurring to nuclear warfare over the territories of Western Europe (most of them belonging to the NATO alliance, and all being substantially more militarized than today), was not deemed just likely, but more as a matter of time.

The БАРС system – The tropospheric network of the Warsaw Pact

In that era of extreme tension, it is not surprising that one of the most sophisticated and expensive assets developed and deployed jointly by all Nations in the Warsaw Pact, of course led by the USSR, came alive. History would cut its life short though, and as soon as the Warsaw Pact disintegrated, as a result of the opt-out from communist dictatorship of all Countries in Eastern Europe, this asset was decommissioned. This system was the tropospheric communication system ‘БАРС’, a Russian word reading ‘BARS’ and meaning ‘snow leopard’. The name stands as an acronym for four words in Russian, which translate into something like ‘Sheltered autonomous radio communication system’.

The idea put forward by the Soviet top-ranking military staff in the early 1980s (prior to the onset of Gorbachev administration) was that of a system capable of transmitting complex orders (not just simple signals, like for opening a bunker door or silo, but articulated messages) in a safe encrypted way, at a long distance and minimizing the chance of a complete breakdown even in case of an enemy nuclear attack. Despite being not new, the concept of a resilient and reliable system, such to allow exchanging significant amount of data without relying on cables, had been tested in earlier stages of the Cold War only for short-radius operations. Mobile transmitters/receivers, loaded on purpose-designed trucks, allowed for a reduction of the risk of a direct hit from an attacker, and for a quick redeployment in case of need. However, for the amount of data and range required for the coordination of a war scenario, involving many different Countries, and geographically encompassing an entire continent, a different system was required, capable of transmitting more massive data flows on longer distances, with a reduced risk of a sudden or complete interruption.

The БАРС system was based on a certain number of stations, scattered over the territory of the Countries of the Warsaw Pact. Each node was built as a bunkerized, manned military installation, featuring high-power, high-frequency fixed antennas emerging from the ground, and an underground shelter protecting all the technical gear required for manipulating the data to be sent or received, interfacing with the other existing local (i.e. national) networks for military and executive governmental communication, and of course managing the tremendous amount of energy required to pump a long-reaching signal into the ether.

Laying on the front line with the West, hosting a Soviet contingent of some hundred thousands troops (see here and links therein), aircraft (see here), missiles (see here) and nuclear warheads (see here), and being a key-ally of the USSR in case of the outbreak of an open war (at least until late 1989), the German Democratic Republic (or GDR, or DDR in German) was clearly included in the БАРС network from the initial drafting phase. Similarly, Poland, Czechoslovakia, Hungary and Bulgaria, and of course the Soviet Union (which included Belarus and the Baltics, and stretched west to Kaliningrad), all had БАРС stations on their territory. Stations were located at a range of a few hundred miles from one another, thus within the range required for each of them to communicate with one or more of the other nodes. Data (e.g. orders, reports or authorizations) input locally could be relayed along the network through intermediate nodes, down to the intended destination node. There were 26 nodes in total, of which four were in the USSR.

The Wollenberg site – Bunker 301 ‘Tushurka’

The GDR in particular had three stations built, all along the border with Poland, and located east of Berlin – namely Station 301 in Wollenberg, at the same latitude of Berlin, Station 302 in Langsdorf, towards the Baltic coast, and Station 303 in Röhrsdorf (near Königsbruck), not far from Dresden in the southeast of the GDR territory. The first among them, the Wollenberg site (codenamed ‘Tushurka’) could communicate with the other two national stations, as well as with Station 207 in Poland, from where data would be transmitted further down the network, towards the USSR.

The site was built by the GDR state, with technical hardware coming from several Countries within the Warsaw Pact, and most of the military hi-tech components manufactured in the USSR. The actual site (similar to its sister sites) was built in the frame of a highly secretive operation. The staff comprised about 60-70 men, the majority of which were military, where about 15% were civil technicians. Maximum security clearance was required, due to the top-secret nature of the installation and of the overall БАРС system. The bunkerized part of the installation was only a component of the larger premises of the base, camouflaged within the trees on the side of low-rising hill.

As pointed out, the immense spending required for setting up this multi-national hi-tech military communication system, which was extensively tested and completely commissioned (as a network) by 1987, did not save it from a quick demise and disappearance. In particular, Station 301 went definitively offline as early as August 1990.

However, the fate of the Wollenberg site was not so sad as that of many former Soviet or NVA (i.e. the East German Army) installations in the GDR. The high-power antennas were torn down, but except from that, little material damage was inflicted to the buildings and bunker on site. The place was basically shut-off and left dormant, until when a society of technically very competent local enthusiasts started a plan to preserve and open it to visitors, as a memorial specimen of the technology of the Cold War years.

A visit to the Wollenberg bunker site reveals a tremendous deal of interesting details, very uncommon to find elsewhere in the panorama of Cold War relics around Europe. Thanks to a careful preservation and restoration work, the bunker has most of its original systems still plugged to the grid and lit-up – some of them are reportedly still working! Even though the communication networks have been severed, the experience in the bunker is really evoking, and the atmosphere – with all the lit-up cabinets, lights, CCTV cameras, 1980-style screens, etc. – closely resembles that of the bygone era when БАРС was operative!

This report and photographs were taken during a private visit to the bunker, carried out in the Summer of 2023.

Sights

A visit to the the installation in Wollenberg starts from the original high-security access gate. As you may quickly notice when passing through it and getting a first view of the site, the state of preservation is exceptional. Except for the lack of military staff around, everything looks mostly like in the years of operation.

A group of soft-construction service buildings and a reinforced multi-entry garage constitute the first – and visible – nucleus of the installation. All buildings are painted in a camo coat.

A former building for the on-site staff has been turned into a permanent exhibition, with memorabilia items from the Cold War years, when the Nationale Volksarmee (or NVA, the Armed forces of the GDR) cooperated with the Soviet Red Army and the national Armed forces of other Countries in the Warsaw Pact.

A meeting room, now employed also for small gatherings, is especially rich of interesting and diverse items, including emblems, books, memorial plates and pennants, as well as TV screens, hi-fi systems and and beamers from the era.

Another room has been set-up as a control center for the base, with an original console and regional maps.

Compared to military bases (for aircraft or tanks), the Wollenberg installation is rather compact, with a main road giving access to most of the (not many) buildings on site, as well as the bunker. Actually, the bunkerized part was built under a low-rising hill, with the antennas originally standing on top of it. Access to the bunker is possible either by climbing uphill on the main road, or through a suggestive original pedestrian tunnel. The latter starts from within the service building itself, and – somewhat unexpectedly, for an underground installation – it climbs uphill, while keeping beneath the surface of the hill side slope. The lower end is guarded by an original CCTV camera.

At the top end of the tunnel you can find the actual access to the bunker. The design and reinforcement level conferred grade ‘D’ protection according to the military standard in use at the time, with grade ‘A’ being the strongest. Access is through an airlock, constituted by two tight doors at the opposite ends of a small vestibule built in concrete. This design allowed protection from the blast of a nuclear device.

Notably, the locking mechanism of the tight doors is Soviet military standard, which can be found in high-value installations like nuclear depots elsewhere in the Eastern Bloc (see for instance here in Poland, and here in Czechoslovakia).

To the visitor with some experience of Cold War installations, it will be apparent from the very start of the tour that the state of conservation of the bunker, including the systems in it, is exceptional, similar to the rest of the Wollenberg site. The original warning lights and the CC-TV camera for identifying people at the entrance are still in place.

Next to the entrance, a control room with technical gear for checking-in can be found – including original dosimeters for radiation and chemicals, mostly Soviet-made. Looking inside these devices is possible, and reveals a great deal of sophistication in the design and realization of the military-grade material from the time.

Showers and sinks for washing, as well as canister for disposing of contaminated clothes, are located in the same area.

Upon getting access to the sealed area of the bunker and passing by the decontamination facility, you find yourself on the top floor of the underground bunker. The high-technology gear required for the transmission/reception of data on the БАРС network, as well as the interface with other national communication systems, required for receiving data, issuing orders, etc. over the territory of the GDR, were located on this floor.

Two symmetrically placed rooms host two twin transmission centers for the БАРС system. A single manned console can be found in each of them, surrounded by electronic cabinets and switches. At a closer look, all the material herein is Soviet made, and labeled in Russian only.

On the wall ahead of the console station is a set of cables, communicating with the antenna and allowing to set the orientation and monitoring its status.

The actual signals transmitted to the antenna, or received from it, traveled along special hollow ducts, with an almost rectangular section. Bundles of these ducts can be found in the ‘Sender’ (which means ‘transmitter’ in English) room, immediately next to the room where the manned console is.

The modulation and demodulation of the signals going out and coming in respectively through the antenna on top of the bunker required some special pieces of electronics, which included the Soviet-designed KY-374 klystron (codenamed ‘Viola’), a component to be found in the cabinets of the ‘Sender’ room.

Following the hollow ducts, it is possible to find where they finally exit the usually manned part of the bunker, bending into receptacles and leading outside. Piping related to other systems, including air conditioning, can be seen as well crossing or running in the same narrow technical corridors.

Beside the consoles monitoring the antenna and the data flowing through it, a kind of operative room for communication can be found, where consoles allowing to receive and forward data and communication to/from all systems are on display. This largely original room features consoles of different levels of technology.

Original explanatory schemes showing the basic features of the БАРС system are on display in that area – in Russian!

An adjoining room features the cabinets required for making all these system work. The cabinets are really many, with a significant share of material manufactured in the USSR. The sight of all these cabinets together is really impressive, and tangibly provides the feeling of a high technology, sophisticated and expensive design. It compares well, but in a largely up-scaled fashion, to the electronics to be found in some special communication bunkers on the western side of the Iron Curtain (see here).

Interspersed with the original arrangement of the cabinets and consoles are some displays of original material. These include specimens of different types of cables for signal transmission – some of them hollow and pressurized, others featuring impressive bundles of thinner wires – the KY-374 klystron, and other once top-secret core components of the БАРС transmission system. Also on display is one of the few remaining parts of the original system of antennas, once on top of the bunker. The antennas were the only part to be physically torn down when the system was decommissioned, upon the demise of the Warsaw Pact and the end of the Cold War.

The bunker was manned by military and technical staff 24/7. Furthermore, as typical for bunkers from the Cold War era, provision was made at a design level to allow the staff to live isolated within the bunker for an extended period of time, in view of the eventuality to face a nuclear fallout scenario.

On the same floor as the technical rooms, the commander of the station had his own private room. This is still adorned with typical Soviet iconography, as well as everyday material from the age when the bunker was operative.

A small canteen, with a kitchen and a modest living room, can be found at the same level. An original storage room has been employed to gather examples of everyday products, like soap, skin care cream, etc., as well as canned food, cocoa, and beverages of all sorts.

This represents a very rich catalog of now largely defunct and forgotten labels, from the age and regions of the Eastern Bloc (and especially from within the GDR). Also on display are bottles of spirits, likely still very good!

The visit proceeds then to the lower floor, which can be reached through a flight of metal stairs.

The lower floor host the plants required for the regular operation of the entire bunker, such to guarantee operational ability even in case of an enemy attack carried out with nuclear, chemical or biological warfare. The air filtering and conditioning system is very modern. Beside typical filtering drums for particles, to be found also in other bunkers (see for instance Podborsko here), you can see a bulky filtering and climate conditioning system, neatly arranged within two parallel square-shaped ducts. Filtering against chemicals as well as biologic agents was carried out employing special active filters.

Sensors for the level of contamination of the bunker air can be found in different rooms. Much material here is standard Soviet-made.

Systems for water pumping and compressed air can be found as well, including compressors, pumps and reservoirs. Looking at the always interesting factory labels in this area, it is easy to find export products of Bulgaria, Romania and other communist dictatorships of the era. Of course, much hardware is also manufactured in the GDR.

Electricity was supplied from the outside grid, yet capability for self-sustaining in case of a grid loss (for instance in case of war) was implemented as well. Three big German-made Diesel generators have been put in place, and are still in an apparently good condition.

Another example of the high technological standard reached in the late Cold War era is represented by the control room for the plants within the bunker. A manned control station, with a console and a direct view of lit-up cabinets, reporting the status of the various systems running in the bunker, compares well with control rooms of large industrial plants in operation today.

Carefully kept in its original status, with many of the electric links and cabinets still working, the sight of this room is especially evoking.

Also on the lower floor are the sleeping rooms for off-duty staff. Typically, this was not employed except for drills, when the bunker could be sealed to simulate operations in case of the outbreak of hostilities.

Back to the upper floor, it is possible to exit the bunker via a stairway and through a side gate. You will find yourself on top of the low-rise hill where the bunker has been dug. Here the concrete base of the crane where the БАРС antenna used to sit are still visible. Notably, these antennas were much smaller than the tropospheric antennas employed for the TROPOSCATTER system of NATO. This was the result of a different bandwidth employed for transmissions. Therefore, even in the days of operation, the antennas on top of the bunker were not as sizable as those of TROPOSCATTER installations (which were enormous in size).

Looking closely, in the top area of the installation, the duct for supplying the Diesel oil tank of the bunker can be found, similar to sensors for radiation and other atmospheric parameters (similar to what can be found also in other nuclear-proof bases, for instance here). These allowed to monitor the conditions of the outside air, detect an attack and trigger or manage the sealing of the bunker in case of need, by locking all the tight doors.

This access to the bunker is fenced by the original electrified fence, severing this area from the rest of the installation through a further layer of security.

All in all, a visit to the Wollenberg bunker offers an incredible insight in a fascinating and crucial field of warfare – data and communication exchange – as well as a lively and evocative display of a late Cold War hi-tech installation from the Soviet side of the Iron Curtain!

Getting there & Visiting

The German name of the Wollenberg bunker is ‘Militärhistorisches Sonderobjekt 301 Wollenberg’. It can be reached very easily with a car. It can be found in the open countryside along the regional road 158, driving about 35 miles (about 1 hour) northeast from downtown Berlin towards Poland. The exact location is between the small village of Höhenland (~4 miles) and the more sizable Bad Freienwalde (~6 miles). There is a large parking area immediately next to the road, giving direct pedestrian access to the premises of the former military installation. Despite being placed very conveniently, the site is rather elusive when passing by, since it is hidden in the trees and not directly visible from the road. The address corresponding to the place in Google Maps is Sternkrug 4, 16259 Höhenland. The inconspicuous village of Wollenberg, giving the name to the installation, is just nearby, but it is not crossed by the regional road, and it should not be employed for pointing this destination with a nav.

The Wollenberg bunker is a listed historical installation. It is perfectly maintained, privately managed, and it can be regularly accessed with guided tours. These are offered typically one day per week in the summer, or by prior arrangement. Possibly the best option for getting the most out of your visit is getting in contact with the group of very knowledgeable enthusiasts running the place. The official website is here (do not be discouraged by the ‘static’ appearance of the website, they are very active, and they shall typically answer your inquire).

My visit was planned by initiative of Dr. Reiner Helling (see also here), and we visited in a group of three, including the guide (Dr. Michael Schoeneck, a former engineer, with a profound knowledge of any technical aspects related to this installation), which happened to be a perfect option for touring also the narrowest receptacles of the bunker. Visiting in groups too big may be not advisable, since the rooms and corridors are rather narrow, and the place may turn overcrowded for interacting with the guide and for taking good pictures. I think the visit – including the technical content – may be tailored to the needs of the audience. For technical-minded subjects, historians and former military, a visit may take about 2-3 hours (the latter was my experience). In my case, the guide could understand but not speak fluent English, yet Dr. Helling could translate with ease all the explanations. Of course, if you have at least a basic knowledge of German and of the technical material you are looking at, this may simplify your visit, which is in any case highly advisable for those interested in military technology and the Cold War.

Heading to Berlin or the former GDR? Looking for traces of the Cold War open for a visit?

A Travel Guide to COLD WAR SITES in EAST GERMANY

Second Edition - 2024

DON'T LEAVE IT AT HOME! AVAILABLE in PAPERBACK or KINDLE from your national Amazon store!
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amazon.it | amazon.fr | amazon.co.jp

Herdla Torpedo Battery – Defending Bergen in WWII and the Cold War

Despite overshadowed by the natural beauties of Norway, the heritage of the rich war history of this Country would really deserve a dedicated trip. Thanks to its geographical location, this Scandinavian Nation had a primary strategic role both in WWII and the Cold War.

Hitler’s Third Reich military forces conquered Norway early in WWII (Spring 1940), gaining an effective stronghold for launching sea and air patrolling missions over the Norwegian Sea and the northern Atlantic. The long coastline stretching from the Skagerrak strait up to North Cape was made impenetrable to enemy invasion, building anew a capillary network of fortifications – the Atlantic Wall. This masterpiece of military engineering was based on an extensive catalog of reinforced concrete standard elements (Regelbau in German), ranging from fortified casemates to radar towers, to observation and target range finding stations, to bunkerized gun batteries, etc. These elements were assembled in larger fortified compounds, placed in key strategic locations along the coast or in the narrow firths reaching to major ports and towns, like Bergen or Trondheim.

Typically run by the Kriegsmarine (Navy) or Luftwaffe (Air Force), these forts may comprise measuring stations, anti-shipping guns, anti-aircraft cannons, plus barracks, services, ammo storages, and even airfields in some cases. They were built not only in Norway, but having been originally planned by the Third Reich to protect the entire coast of conquered continental Europe, they were erected along the shoreline also from Denmark down to France.

As a matter of fact, many of the Norwegian fortresses of the Atlantic Wall rank today among the most massive and well-preserved of the entire line (see here for some highlights).

But the war history of Norway, and of its mighty military infrastructure, didn’t stop with the end of WWII. With the start of the Cold War, Norway became a NATO founding member, and once again of great strategic value. It found itself in close proximity to the USSR, and with a long coastline facing the sea corridor taking from the highly-militarized Murmansk and Kola Peninsula (see here) to the northern Atlantic.

Most of the Atlantic Wall forts, especially anti-shipping and anti-aircraft gun batteries, were obsolete by the 1950s, and were soon deactivated. Some were abandoned or, when retained by the Norwegian military, they were modified to cover new functions.

In a few cases, the original mission of the site by the Third Reich was retained by NATO forces in the Cold War. This is the case of the torpedo battery in Herdla.

The fortress of Herdla was a major strategic fort in the Atlantic Wall, allowing to keep a watch on the entry point to the inner waters leading to the large industrial and military port of Bergen. Thanks to the morphology of the area, featuring a rare spot of flat land nearby a steep and rocky cliff, an airfield was installed by the Third Reich besides a set of bunkers, effectively hidden in the rocks. A land-based torpedo battery, consisting of a range-finding and aiming station and torpedo-firing tubes, was part of the fort.

During the Cold War, it was decided that the torpedo battery could be still a valuable asset, and Herdla was retained by the Norwegian military – by comparison, the airfield, too short for the requirements of the jet-era, was not. Over the years, the torpedo battery was potentiated to keep up-to-date against the technological offensive capabilities of the Eastern Bloc, and to exploit the most modern identification and surveillance techniques.

The torpedo battery was part of a larger naval fort, which controlled also the barrier of sea mines implemented to stop a sea-based intrusion towards Bergen.

As a matter of fact, the area control functions and the offensive capability of Herdla were retained until the early-2000s, when the fortress was deactivated following the end of the Cold War and defense budget cuts.

Luckily however, the often neglected Cold War chapter of warfare history has in Herdla a valuable asset – an accurately preserved fortress regularly open for a visit. A modern visitor center welcomes the more curious travelers, leaving Bergen towards the remoteness of the coast. It retraces the WWII heritage of the Herdla site, thanks to an exhibition centered around an original Focke-Wulf FW190, recently salvaged from the bottom of the sea, and with a special history to tell. Then a visit to the battery, looking like it had just been left by the military staff, is a unique emotion for both the specialized war technology enthusiasts and the general public as well.

The following report and photos is from a visit taken in Summer 2022.

Sights

As outlined in the overview, the Herdla site today is centered on two major highlights. One is the visitor center, with the preserved relic of a unique Luftwaffe Focke-Wulf FW190. The other is the former torpedo battery and Navy area command bunker, Norwegian facilities installed during the Cold War in bunkers dating to the Third Reich era.

Visitor center & Focke-Wulf FW190 exhibition

The relic of a Focke-Wulf FW190 A-3 German fighter from WWII is hosted in a dedicated room, where a scenic lighting makes this impressive exhibit literally shine.

This exemplar of the iconic Third Reich fighter, produced in some thousands examples, and now almost impossible to find especially in Europe, is ‘Gelbe 16’ (which can be translated in ‘Yellow 16’) of 12./JG5, and its history is deeply related to Herdla.

It took off on December 15th, 1943, from the airfield the Luftwaffe had established on the flat area now lying ahead of the visitor center, at the time a very active German airbase.

Following troubles with the engine, it ditched in the cold inner water near the island of Misje, some ten miles south of Herdla, the pilot being able to abandon the doomed aircraft, and being saved by local fishermen – and returned to the Luftwaffe, who had a Norwegian resistance prisoner released in acknowledgment.

The aircraft sank to the bottom of the sea, but its memory was not lost by some of the locals, who clearly remembered the events. The Focke-Wulf remained there for 63 years, but it was finally located and pinpointed by the Norwegian Navy, instigated by local interest, in 2005. After preparatory work – including exploration dives, to assess the condition and to set-up recovery operations – the fairly well-preserved wreck was lifted to the surface on November 1st, 2006, and loaded on a tug. Conservative restoration work then took place in Bergen.

Instrumentation and the machine guns were all recovered, together with many further fragments of equipment. Interestingly, evidence of repaint was found during conservation, retracing some previous assignments. Yet the history of this very exemplar remains difficult to write in its entirety.

Finally, following completion of conservation works, a new home for the aircraft was prepared in Herdla, where a hangar was built anew – and this is where you can see it today.

The aircraft is in an exceptional state of conservation, considering it spent 63 years in sea water. The fuselage, wings and tail are not significantly damaged, with just some paneling having disappeared on tail control surfaces, due to corrosion. The swastika on the vertical stabilizer is still perfectly evident, like other painted details.

The propeller blades are all bent downstream, as typical for an emergency landing carried out without the landing gear and the engine still running. The tail wheel is there with its original tire, the emblem of the German brand ‘Continental’, still in business today, being clearly noticeable.

The instrumentation from the pilot’s control panel has been put on display separately. Also a gyroscope has been found. Everything is only slightly damaged. Similarly, the two machine guns, dismounted prior to lifting the aircraft from the sea, are little damaged, and displayed with some ammo.

Complementing the exhibition are a few other pieces from other wrecks, as well as some quality scale models and dioramas portraying Herdla in the days of Third Reich tenancy.

Torpedo Battery

Access to the torpedo battery, which was built in WWII just above sea level, is from a gate on the land side. From outside, the bunkers in the fortress of Herdla appear especially well-deceived in the rocks of the cliff.

What is seen today inside, however, dates to the years of Norwegian tenancy. The facility was updated in several instances during the Cold War, the last in the 1990s. Immediately past the gate, you get access to a modern and neat mechanics shop, where a partly dismounted torpedo allows to have a suggestive look inside this marvelous weapon.

Interestingly, Norway inherited and went on operating a significant number of German G7a (TI) torpedoes. This was the standard torpedo employed by the Kriegsmarine since 1934, and with some modifications (‘TI’ standing for ‘first variant’, the later variants bearing other codes), for the full span of WWII.

Propulsion power for this torpedo was from a piston engine, fed by high-pressure vapor obtained by the combustion of Decaline with compressed air stored onboard, mixed in a heater (i.e. a combustion chamber) with fresh water, similarly stored in a tank. The resulting mixture fed a 4-cylinder radial piston engine, driving two counter-rotating propellers. The exhaust in the water produced a distinctive contrail of bubbles, and the presence of a high-frequency moving mechanism had the side-effect of a significant noise emission. The head of the cylinders can be clearly seen in the dismounted exemplar.

Guidance was provided by rudder steering controlled with the help of gyros, whereas depth was controlled via a mechanical depth sensor. The torpedo could stay close to the surface or keep an assigned depth. In WWII the torpedo had no homing device – i.e. it was ‘blind’, thus requiring carefully putting it on a target-intercept trajectory. It could however cover pre-determined trajectories of some sophistication. The set-point selection for guidance and the yaw regulation gyro assembly have been taken out of the torpedo, and can be checked out in detail.

The range could be selected before launching, and was traded off with speed. It could be between 5.500 and 13.200 yards, and the speed ranged between 44 kn and 30 kn correspondingly. The German origin of the torpedo on display is betrayed by the writings in German on some parts.

Leaving the workshop through a gate towards the inner part of the bunker, a roomy supply storage area can be found, with some interesting material including torpedo parts, as well as a torpedo launching cannon.

This item represents the primary way of launching torpedoes in the early Cold War from land-based batteries or ship decks. This was a technology inherited from WWII, when coastal batteries of the Atlantic Wall ejected torpedoes from slots in the bunker wall, shortly above the surface of the water, employing cannons similar to this one (which dates from the Cold War period), thanks to a burst of compressed air. This cheaper, but less ‘stealthy’ and accurate launching procedure, was replaced by underwater launching tubes only over the years of the Cold War, featuring an increase in the level of sophistication of warfare. Correspondingly, the slots in the side of the torpedo battery bunker facing the water were bricked up, and torpedo cannons were retained mostly for use from the deck of warships.

From the storage room you get access to the core area of the battery. This is through a decontamination lock, with gear for anti-contamination testing, including paper strips for checking contamination from poisonous gas.

The battery features two diesel generators for electric power, employed in case of disconnection from the regional grid.

Less usual – for a military facility – is the presence of two air compressors. Compressed air is relevant for torpedo operation, being employed for the launch burst from the torpedo tube, as well as for propulsion and gyros in the G7a torpedo. The air compressors in Herdla are made by Junkers, solid German technology from 1961!

A few bunkerized resting rooms for the staff manning the battery can be found in the same area, besides the power/compressed air supply room and the torpedo room. The resting rooms are minimal as usual, with suspended berths, and much personal military equipment on display – coats, blankets, medical kits, and more technical material.

Finally, the core of the battery is the torpedo room. This is much longer than wider, access is via the short side. In the Third Reich years, the launching slot was on the short side to the opposite end of the room, right above the water. Today, this slot has been bricked up, and there is no window at all.

The torpedoes are aligned on racks along the long sides of the room. The launching system is via two underwater tubes, which are accessed via obliquely mounted hatches, one to each side of the room at the level of the floor. The section of the racks closer to the entrance door is actually a pivoting slide. The slide could be pitched down, thus allowing the torpedo to slip through the hatch in the firing tube. The original launch control console can be found to the right of the access door – in a mint condition, it looks really like it had just been put in standby following a drill!

Over the years, the stockpile of G7a TI torpedoes was upgraded especially in terms of guidance. The major modification was the adoption of wired control. This is based on a thin electric cable unwinding as the torpedo proceeds along its trajectory, keeping it linked with the launching battery. This upgraded model is called G7a TI mod 1. Control via a steering joystick and trajectory monitoring system could provide manual guidance to the torpedo, thus sharply increasing the chance of target interception. This technology is still in use today. Wire tubes can be found on top of the rudder of torpedoes.

Besides the G7a, Herdla battery received the TP613 torpedo, a weapon developed in Sweden in the early 1980s from previous designs. Exemplars of this torpedo, still in use, are visible in the torpedo room. In terms of mechanics, the piston engine of this torpedo is powered by the reaction of alcohol and Hydrogen-peroxide. In terms of guidance, this torpedo features improved wired communication for guidance and power setting (i.e. changing torpedo speed during the run), as well as passive sonar homing. A dismounted section exposing the engine can be found on display.

The wire tube installation on top of the rudder is featured also on this model, and examples of the wire are on display.

The original guidance console, made by Decca, with a prominent joystick on it, is on display as well!

Training and proficiency checks are typically carried out without a warhead, but with an instructional head. Distinctively painted in shocking red, and with powerful lights in them – to show their position to simulated targets during training exercises, when needed – these are on display in a number. Since the torpedoes, just like missiles, are very expensive, a way of recovering them after instructional use has been envisioned, in the form of inflating bags coming out of the head, increasing the buoyancy of the emptied torpedo and forcing it to surface when reactants tanks are empty and power is off.

Offensive warheads can be exchanged with dummy ones for training, bolting them to the body of the torpedo, which remains totally unchanged. A warhead with a 600 lbs explosive load, triggered by a proximity pistol, was typically put on G7a torpedoes. The proximity pistol was made of four petals, which on contact with the target were bent towards a conductive metal ring around the nose cone of the torpedo, closing an electric circuit and triggering the explosion.

Leaving the torpedo room and the bunker is via the same way you came in.

Sea Mines & Area Control Center

But your visit is not over. As mentioned, the Herdla coastal battery hosts an area control center, with provision to manage target detection facilities and the minefields in the waters around Bergen.

This part was built in a facility strongly potentiated with tight doors, typical to the shockwave-proof military construction syllabus of the Cold War. A sequence of roomy vaults carved in the rock hides a number of containerized modules, together with an exhibition of sea mines and related apparatus.

Most notably, an L-type Mk 2 moored mine and a Mk 51 bottom mine are on display, with a understated control panel. The latter is actually a portable controller for triggering the mines. Already before WWII, sea mines were often put on the bottom of the sea in shallow waters, or moored in deeper waters, to control access inner waters, firths, ports, etc. The Germans made extensive use of this technique in Norway, and following WWII this strategy was inherited by Norway to protect its waters from (primarily) Soviet intrusion.

Despite contact mines were still popular in WWII, they have been surpassed and gradually replaced already in that age by proximity mines, based on noise and – especially – magnetic sensors. Today, proximity fuses activated by the magnetic field of ships or submarines passing nearby are standard technology. Onboard electronics allows to distinguish between the magnetic signature (i.e. fingerprint) of different ships, thus avoiding any issue for civilian or friendly traffic, and activating only against enemy shipping. Degaussing techniques – i.e. the ability of military ships to hide their signature – have forced to improve detection technology, which is today extremely sophisticated.

Furthermore, for the protection of ports and friendly waters, sea mines are typically controlled and triggered by hand, upon detection and localization of enemy shipping, by means of dedicated detection facilities on land or water. This improves precision and allows more flexible defensive-offensive tactics, since a human chain of command has control on the minefield, instead of a pre-determined computer program.

To trigger the mines, consoles like that on display are employed, where a trigger for each mine allows precise control over the minefield.

The first containerized control center hosts a similar, yet much more modern, dedicated console. Everything in this movable control center is very neat, and really looking like reactivation might take place in just moments! Of interest is also the situation map, covering the area around Herdla and the water inlet to Bergen.

A nearby container reveals berths and a small living area for stationing staff.

Yet another container hosts a complete situation room covering the area. Similar to the coastal battery in Stevnsfort, Denmark (see here), a careful eye was constantly overlooking the shipping in the area.

In the same container, a console for steering torpedoes, more modern than that previously seen in the torpedo battery, is on display.

All in all, Herdla is a one-of-a-kind destination, of primary interest for those interested in Cold War military history, enjoyable and easy to visit. Totally recommended for everybody with an interest in history, with much to see and learn for the kids as well.

Getting there & Visiting

Herdla fortress features an official visitor center with a large parking area, and amenities including a small restaurant and a shop. The official website is here. It can be reached about 27 miles north of central Bergen, roughly 45 minutes by car. The address is Herdla Museum, Herdla Fort, 5315 Herdla.

The torpedo battery and control bunker can be visited only on a guided tour. Visiting from abroad, we scheduled an appointment, and were shown around by the very knowledgeable guide Lars Ågren, a retired officer of the Royal Norwegian Navy. He joined the Navy in the late 1970s, in time to gain a substantial, hands-on Cold War experience during the final, high-tech part of that confrontation. He was promoted to tasks in the NATO headquarters in Belgium, later returning to Norway, and totaling more than 37 years in service. He is strongly involved in the management of the Herdla site. Chance is for you to embark on a visit with this guide, or other very competent guides who will satisfy the appetites of more committed war technicians and engineers, being capable of entertaining also the younger public as well.

A visit to the torpedo battery and control center may last about 1 hour. Seasonal changes to opening times may apply, as common in Northern Countries, therefore carefully check the website.

Bunker Kossa – A Preserved Cold War Military Bunker in the GDR

Heading to Berlin or the former GDR? Looking for traces of the Cold War open for a visit?

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The history of the underground installation in Kossa-Söllichau begins in the 1930s under Hitler’s rule.

In 1935, an affiliated company of the German chemicals giant WASAG, named Deutsche Sprengchemie Moschwig and devoted to the mass production of explosives for warfare use, had a new plant built in the rather uninhabited forest area between Leipzig and Wittenberg.

The plant, codenamed ‘Beech’ (or ‘Buche’ in German), was updated over the years and turned into a major production center for several models of shells and high-explosive charges. A primary contractor of the German Army, the company also held relevant patents, including one for hollow charge grenades.

By the end of WWII in April 1945, when the area fell under Soviet control and production was halted, the plant counted 3.600 employees, and had a production capacity of around 600.000 ammunitions per month. It had been provided with a dedicated road and railway connection, and built mostly underground, with several concrete bunkers surfacing from the grassy terrain around.

Following the Potsdam agreement (July 1945), the area was completely flattened by the hand of the Soviets, similar to some other production facilities in Germany. Demolition had been completed by the end of 1947. Following that, the area remained silent for more than a decade.

By the early 1960s, with the Cold War and rearmament in full swing, the the Nationale Volksarmee, or NVA – the short name of the Armed Forces of the GDR – had been long established as an ally of the Red Army. The latter was physically present in Germany with a huge number of troops and war material, having taken over many of the former German bases from WWII (see here or here for instance). However, the GDR clearly had its own Armed Forces, which actually could count on high-quality war material, typically either manufactured in Germany or supplied by the USSR. More and more locations – especially the most secluded and easy to hide – got surrounded by fences, and ended under the control of the NVA for many different purposes.

Deployed on the border with the West, and considered a reliable and well-trained partner by the Red Army, the NVA was included in the war plans conceived in Moscow, intended to unfold in the event of an open war with the neighbor NATO Countries. The NVA had two larger military districts, south of Berlin (III) and north of Berlin (V). In case of war, district III would give birth to a 3rd Army of mixed GDR/USSR forces, to quickly push towards the south-west into Federal Germany (heading to Koblenz), and from there to the Atlantic coast, to be reached in a matter of a few days.

The headquarter of the 3rd Army was in the so-called ‘Mosel’ bunker, an underground command facility near the town of Zwickau, today converted for an alternate use and not visible at all.

An alternate control site, which was also primarily involved in drills and training, was built in the area of the former ‘Beech’ installation, and took the name of ‘Bunkeranlage’ (i.e. bunker installation) Kossa-Söllichau. This site was prepared in the years 1976-79, and consisted mainly of 5 large interred bunkers on the same premises, capable of resisting to tactical nuclear blasts, with up-to-date systems for communication, and an ability to replicate war situations, so as to carry out realistic and complicated tactical simulations and drills. The staff was typically of 400.

Similar to the majority of military assets in Germany – and especially within the super-militarized ex-GDR – Kossa was incorporated in the Armed Forces of reunified Germany (1990), but was soon declared surplus, deactivated and handed over for civilian use.

A society of enthusiasts is today running this former facility, keeping it open for visitors on a regular basis. What makes Kossa an exceptional destination for both the general public and the most committed war tourist as well is the great state of conservation of the entire facility. As it can be seen in the following photographs, taken in Summer 2022, inside the bunkers it is possible to see not only the original structure, but most of the original communication systems, paneling, signs, furniture, lamps, toilets, lighting, wallpaper, etc. making the place a very vivid testimony of the Cold War years.

All in all, this is one of the best surviving specimens of bunkerized NVA sites, and definitely worth a visit for a rich in detail full immersion in the military technology and history of the Cold War years.

Sights

A visit to the Kossa site will start walking past the original inner gateway to the bunkerized part of the complex. The original wall going all around the entire military area has been partly removed, allowing to get direct access to the ‘core’ of the installation by car. Traces of the electrified fence running all around this inner part of the complex are still standing. The entrance to a bunker for the guards can be seen in this area, but this cannot be visited.

The core of the complex with the military bunkers is aligned along a single, mostly straight technical road, built with large concrete slabs. The road track today is the same as in the original pre-WWII complex, and for this reason, it was not camouflaged. Other buildings in the complex, an even the connection roads departing from the main one, are painted in camo coat, for deception in case of overflight by plane or satellite.

The ticket office today is hosted in a large technical building by the entrance. In this area there used to be canteens and other services.

Past the entrance to the bunker area, it is possible to visit five bunkers, which will be listed next.

Computer Bunker

Four out of five bunkers (the exception being the intelligence bunker, see later) are built around the same blueprint. They have a single entrance door, deceived under a small wooden hut. Access to the bunker is via a security and decontamination path. At first you see a big camera at the level of your face, and an intercom panel, all for identification. Next follows a sequence of tight doors, at a close distance from one another, producing three small tight compartments.

In case of nuclear/chemical contamination, faced in wartime, in the first compartment you could take an anti-poison kit, EP-68. Exemplars of this are still in place. In the next compartment you had to throw away all your clothes and belongings, which were put through a hatch to the side. In a third small compartment, you found a shower – a central passage in the decontamination process, even in case of exposition to nuclear events.

Through a last tight door, you could finally enter the clean area of the bunker. Here regular toilets and showers can be found, before going down one level, to the technical part.

Back then, there used to be three levels of air sealing. No air sealing, in regular, no-war/no-drill conditions, meant the decontamination procedure was not activated, and the bunker was ventilated with fresh air. In sealing conditions, typically at war but not under direct attack, the bunker was tight closed, and air was pumped from the outside through huge filtering canisters, purpose designed to stop both smoke and other gases, or poisonous chemicals. On the third level of air sealing, corresponding to an emergency condition (e.g. a direct attack), no air was pumped from the outside, and special filters capturing carbon dioxide allowed to carry on for a limited amount of time – reportedly a shorter time than granted by food or water storage.

Filters for the air conditioning system (sealing level 2) and for adsorbing carbon dioxide (sealing level 3) were made in the USSR. Those for carbon dioxide are scattered around the bunkers, and feature a rather vintage Soviet look, with a prominent five pointed star on top. The label carry the assembly year, in most cases the early 1970s.

Once downstairs, you can appreciate the construction of the bunker lower level, based on prefabricated concrete frames. The bunkers in Kossa were capable of resisting blasts typically from smaller tactical devices, and were ranked at the fifth strength level (level ‘E’), the first level being the strongest.

Here a few rooms are still perfectly preserved with computers, of which the most impressive is a mainframe AP-3, working with magnetic tape. The GDR could boast a top-notch electronic industry within the Eastern Bloc, and all consoles and electronics in Kossa bear local labels.

The purpose of the computers, deemed so relevant to create a bunker specifically for them, was the fast elaboration of all information from the war theater. The latter was both local and global, since thanks to the links reaching the site through the intelligence bunker (see later), information of any kind could be elaborated, allowing the constant updating of operation maps, and the monitoring of all war assets. In drills, the computation capacity of the the system allowed to simulate events, thus forming the core of war-game operations.