La Coupole
Encyclopedia
La Coupole codenamed Bauvorhaben 21 (Building Project 21), Schotterwerk Nordwest (Northwest Gravel Works) or Wizernes, is a Second World War bunker complex built by the forces of Nazi Germany
between 1943 and 1944 to serve as a launch base for V-2 rocket
s against London and southern England. It is situated in the commune
of Helfaut
in the Pas-de-Calais region of northern France
, about 5 kilometres (3.1 mi) from Saint-Omer
.
Constructed in the side of a disused chalk quarry, the complex comprised an immense concrete dome, to which its modern name refers, above a network of tunnels that were to house the launch facilities and crew quarters. The facility was intended to store a large stockpile of V-2s, warheads and fuel and to be able to launch missiles against London and southern England at a high daily rate. Heavy secret weapons sites like Wizernes, Watten, Mimoyecques and the Wasserwerks of St Pol, Desvres, were collectively called by the Organization Todt the "Special Constructions", in German.
However, due to repeated heavy bombing by Allied forces carried out as part of Operation Crossbow
, the Germans were unable to complete the construction works and the complex never entered service. It was captured by the Canadian Army in September 1944 and was subsequently abandoned. The complex remained derelict and abandoned until the mid-1990s. In 1997 it opened to the public for the first time after being redeveloped into a museum. The tunnels and the main exhibition area under the dome tell the story of the German occupation of France during World War II, the V-weapons and the history of space exploration
.
(LOX) – more, in fact, than was available from existing production sites in Germany and the occupied countries. New sources of LOX were required, situated close to the missile launching sites to reduce as far as possible the loss of propellant through evaporation. The missile's operational range of 320 kilometres (198.8 mi) meant that the launch sites had to be located fairly close to the English Channel
or southern North Sea
coasts, in northern France, Belgium
or the western Netherlands
.
Because of the complexity of the missile and the need for extensive testing prior to launch, the V-2's designers at the Peenemünde Army Research Center favoured using heavily defended fixed sites where the missiles could be stored, armed, fueled from an on-site LOX production plant and launched. This was opposed by the German Army and the V-2 project's head, Major-General Walter Dornberger
, who were concerned that the sites would be vulnerable to aerial attack by the Allies. The Army's preferred option was to use Meillerwagen
s, mobile firing batteries, which presented a much smaller target for the Allied air forces.
The Army was nonetheless overruled in March 1943 by Adolf Hitler
. His long-standing preference for huge, grandiose constructions led him to order the construction of a massive bunker (now known as the Blockhaus d'Éperlecques) in the Forest of Éperlecques
near Watten
, north of Saint-Omer. The bunker was soon spotted by Allied reconnaissance and on 27 August 1943, a raid by 187 B-17 bombers wrecked the site before it could be completed. A surviving portion was re-used by the Germans as a LOX production facility.
, south-west of Saint-Omer some 12 kilometres (7.5 mi) south of the Watten bunker, had already been designated for use to store missiles in tunnels bored into the chalk hillside. It was located near the Aa river
alongside the Boulogne–Saint-Omer railway line, about three-quarters of a mile (1 km) from Wizernes station. The Germans had already undertaken major work in August 1943 to lay extensive railway sidings to connect the quarry to the main line.
On 30 September 1943, Hitler met with Albert Speer
, the Minister of Armaments and War Production, and Franz Xaver Dorsch
, the chief engineer of the Todt Organisation, to discuss plans for a replacement for the out-of-commission Watten facility. Dorsch proposed to transform the Wizernes depot into a vast bomb-proof underground complex that would require a million tons of concrete to build. It would be constructed within a network of tunnels to be dug inside the hillside at the edge of the quarry. A concrete dome, 5 feet (1.5 m) thick, 71 metres (232.9 ft) in diameter and weighing 55,000 tons, would be built over the top of the central part of the facility to protect it from Allied bombing. Beneath it, about 7 kilometres (4.3 mi) of tunnels were to be dug into the chalk hillside to accommodate workshops, storerooms, fuel supplies, a LOX manufacturing plant, generators, barracks and a hospital.
A standard gauge railway tunnel, codenamed Ida, was to be built on a curving path that would connect it with both the east- and west-bound main line railway, allowing trains to run straight through the complex without needing to reverse or be turned around. This would serve as the main unloading station, where missiles and supplies would be offloaded onto trolleys that would transport them into the connecting galleries Mathilde and Hugo. Hugo connected in turn with Sophie, a dead-end railway tunnel branching from the main line into Ida. Each of the main tunnels had a number of unnamed side tunnels of the same dimensions as the main tunnels and up to 90 metres (295.3 ft) long. The central feature of the complex was a huge octagonal chamber directly under the dome. It was never completed but would have been 41 metres (134.5 ft) in diameter and up to 33 metres (108.3 ft) high. A number of intermediate floors, possibly as many as ten, would have been built up the sides of the chamber.
The western side of the chamber opened onto two tall passageways called Gustav and Gretchen. Each was to have been protected by bomb-proof doors made of steel and concrete. The passageways were to be 4 metres (13.1 ft) wide and at least 17 metres (55.8 ft) high and were angled in a Y-shape, exiting into the quarry. Open-air platforms for launching rockets would have been situated at the end of each passageway. The two passageways were angled at 64° 50' and 99° 50' west of north respectively – not aligned with any probable target but merely permitting the rockets to be transported to sufficiently widely separated launch pads.
The facility was designed, as was its predecessor at Watten, to receive, process and launch V-2 rockets at a high rate. Trains carrying V-2s would enter the heart of the complex through the Ida rail tunnel, where they would be unloaded. A large number of V-2s could be stored in the side tunnels; LOX would also be produced on-site ready for use. When the time came, the rockets would be moved into the octagonal preparation chamber where they would be lifted to a vertical position for fueling and arming. From there they would be transported on motorised launch carriages through the Gustav and Gretchen passageways and out to the launch pads, ready to be fired.
The priority target for the V-2s was London, 188 kilometres (116.8 mi) away, that Hitler wanted to see pulverised by the end of 1943. The Allies were alarmed when a photo interpreter found out that part of the complex was aligned within half a degree of the Great Circle
bearing on New York
, though Albert Speer denied after the war that there had been any intention of using Wizernes as a launch site for intercontinental missiles such as the planned A10.
Although physically separate, another facility built in nearby Roquetoire
was an integral part of the Wizernes complex. Umspannwerk C was built to house a Leitstrahl radio command guidance system which could be used to send course corrections to missiles launched from Wizernes to fine-tune their trajectory during the launch phase.
bunker had been put out of commission, Hitler agreed to convert the Wizernes storage bunker to a launching site. in October 1943, Speer noted that "he [the Führer] is not convinced that the site will ever be finished". Construction work began in October 1943 and the building of the dome commenced in November. It proved a slow process because of constant air-raid warnings, which stopped work 229 times in May 1944 alone. The constant delays were a source of major frustration as they meant that the Todt Organisation could not provide a completion date. Dornberger's representative commented: "This means that no date can be set for the specialised launching gear and machinery to be installed. General Dornberger has asked Field Marshal
von Rundstedt
to decide whether it would not be better to abandon the whole project."
Dornberger reported that he considered the structure to be useless. However, this was contradicted by Todt engineers and fortification experts, and by Hitler himself, whom Speer recorded was "infuriated by this frivolous way of reporting things." In response to Hitler's desire to see the site completed the workforce was built up substantially from 1,100 in April 1944 to nearly 1,400 by June. About 60% of the workers were Germans; skilled workers, such as miners from Westphalia
, were recruited to excavate the tunnels and build the dome. The remainder were principally Frenchmen conscripted by the Service du travail obligatoire
(STO), plus Soviet prisoners of war. The project was overseen by several large German construction companies, with Philip Holzman A.G. of Frankfurt am Main and the Grossdeutsche Schachtbau and Tierbohr GmbH serving as the chief contractors.
One of the most difficult challenges faced by the Germans was that of how to construct the great dome while under regular air attack. The dome's designer, Todt Organisation engineer Werner Flos, hit upon the idea of building the dome first, flat upon the ground, and then excavating the soil underneath it so that the construction works below would be protected against aerial attacks. A circular trench was excavated on the top of the hill above the quarry to an outside diameter of 84 metres (275.6 ft). The dome was built within this trench and the galleries and octagonal preparation chamber were excavated below.
As an additional bomb-proofing method, the dome was surrounded by a bomb-proof "skirt" or Zerschellerplatte of steel-reinforced concrete, 14 metres (45.9 ft) wide and 2 metres (6.6 ft) thick. This was supported by a series of buttresses, which were not tied into the dome itself, above the entrances to the Gustav and Gretchen tunnels. Another concrete structure was tied into the skirt to the northwest of the dome, which was perhaps intended for use as an observation and control tower. A separate underground building was constructed on the western side of the quarry to serve as a hospital and as offices for the engineers. A Decauville
narrow-gauge railway was installed on the quarry floor to transport supplies from the main line to the construction site.
A cube-shaped concrete building was constructed on the top of the hill, next to the dome. This was intended to be used as the bomb-proof outlet for a ventilation and air conditioning shaft – an essential element for a facility where dangerous and explosive gases were expected to be used in large quantities on a daily basis. It was never finished and when the Allies captured the site they found that the ventilation shaft had not been fully excavated. The building survived the bombing intact and is still prominently visible today.
Unlike its sister site at Watten, there was no on-site power plant; electricity at Wizernes was provided by a connection to the main electric grid, with consumption estimated at between 5,000–6,000 kVA
.
reported that the Germans had begun constructing the concrete dome and were undertaking tunnelling works in the east face of the quarry. However, it was not until the following March that the Allies added the site to the list of targets for Operation Crossbow
, the ongoing bombing campaign against V-weapon sites that had already wrecked the Watten bunker and numerous V-1 launching sites. Over the next few months, the USAAF and RAF carried out 16 air raids involving 811 bombers that dropped some 4,260 tons of bombs. The bombings caused destruction across a wide area, killing 55 residents of the nearby village of Helfault.
Conventional bombing raids only achieved a single bomb hit the dome itself, causing negligible damage. However, in June and July 1944 the RAF began attacking the site with 6-ton ground-penetrating Tallboy bombs. The external construction works were completely wrecked by the bombing and one Tallboy landed just beside the dome, blowing out the entire quarry cliff face and burying the entrances to the Gustav and Gretchen tunnels. The entrance to Sophie was also buried, leaving Ida as the only entrance to the facility. The dome was unscathed but the buttresses supporting the protective Zerschellerplatte were dislodged and slid partway down into the quarry. Serious damage was also caused to the tunnels beneath the dome. The damage made it impossible to continue work on the site. Dornberger complained: "Persistent air attack with heavy and super-heavy bombs so battered the rock all around that in the spring of 1944 landslides made further work impossible." His staff reported on 28 July 1944 that, although not hit by the Tallboys, "the whole area around has been so churned up that it is unapproachable, and the bunker is jeopardised from underneath."
In May 1944, the 953 (Semi-Mobile) Artillery Detachment started Abteilungen (firing detachment) training at Blizna
in southeastern Poland for operations at Wizernes. Consisting of one technical and two operational batteries, the detachment was expected to launch up to 50 rockets daily from Wizernes. However, they never got the chance. On 3 July 1944, the Oberkommando West
gave permission to stop construction at the heavily damaged Watten and Wizernes sites. On 18 July 1944, Hitler abandoned plans for launching V-2s from bunkers and authorized the downsizing of the Wizernes bunker into a LOX production facility. However, these plans were overtaken by the liberation of Northern France consecutive to the Normandy landings. The site was finally abandoned and inspected by British engineers on 5 September.
, the head of the British "Crossbow Committee" investigating the V-weapons programme, ordered the constitution of a Technical Inter-Services Mission under Colonel T.R.B. Sanders
. It was given the task of investigating the sites at Mimoyecques, Siracourt, Watten, and Wizernes, collectively known to the Allies as the "Heavy Crossbow" sites. Sanders' report was submitted to the War Cabinet on 19 March 1945.
The purpose of the Wizernes site had been unclear prior to its capture but Sanders was able to deduce its connection with the V-2 from the dimensions of the complex and some intelligence information that his team had been able to retrieve. Sander's report concluded that it was "an assembly site for long projectiles most conveniently handled and prepared in a vertical position". He conjectured the approximate length of the projectiles from the height of the Gustav and Gretchen tunnels, though he noted that there was some doubt about the height of the doors at the tunnel entrances. Segments of the doors had been recovered from a storage dump near Watten railway station, but were incomplete. The maximum size of the projectile could thus have been between 17 metres (55.8 ft) and 24 metres (78.7 ft) in length and 4 metres (13.1 ft) in breadth. (This was substantially larger than the V-2, which measured 14 metres (45.9 ft) long and 3.55 metres (11.6 ft) wide.) Two witnesses interviewed by the Sanders team reported "an intention of firing a projectile 18 metres long." Sanders noted that "the dimensions of the site make it suitable for the A.4 (V-2
) rocket, but the possibility of a new rocket up to half as long again as the A.4 and twice the weight cannot be ruled out."Although the V-2 rocket
at 14 metres (45.9 ft) long could have been carried by a car through the Sanders-identified height , the Aggregate series#A10 A10 New York rocket design was too tall--even without a rail carrier--at 26 m (85.3 ft). He concluded that much of the site was becoming unsafe due to the progressive collapse of timbering and recommended that the tunnels and workings under the dome should be destroyed to prevent subsequent accidents or misuse.
The site reverted to private ownership after the war. As the quarry had long since been worked out, it was abandoned. The tunnels were not destroyed but were sealed off, though at some point they were reopened by local people and could be entered; the octagon remained sealed off with a ceiling-to-floor barricade. The quarry itself remained in almost the same condition as it had been in 1944, with sections of railway track still in place on the quarry floor. The hospital section remained relatively intact and was used by the local gendarmes as a shooting range.
earmarked 10 million FF
to develop the site as a tourist attraction for the Nord-Pas-de-Calais region with the intention of establishing a Second World War museum there. The plan was publicised in a special open weekend on 20/21 June 1987, attended by over 20,000 people, in which the dome's designer Werner Flos met Professor Reginald Victor Jones
, a surviving member of the "Crossbow Committee", at Wizernes. The Ida tunnel and side chambers were opened to the public and used for an audio-visual exhibition of the site's history.
Local historian Yves le Maner was charged with the task of developing the project while a feasibility study was conducted into the possibility of completing some of the original excavation work to make the site safe for public access. The plans were approved in 1993 and the site was bought by the Commune de Helfaut. The following year, the Conseil Général du Pas-de-Calais acquired the site. The 69 million FF project (£7.5 million at 1997 prices) was largely underwritten by the Conseil Général, which provided 35 million FF, with another 17 million FF coming from the regional council. The European Community provided a further 12 million, the French State provided 3 million FF and the Saint-Omer municipal administration funded the remaining 1 million FF; a number of private shareholders were also involved. The Societé d'Equipement du Pas-de-Calais was contracted to carry out the development work, which involved excavating a further two metres (six feet) beneath the dome, clearing out and completing the unfinished concreting of some of the tunnels, building an exhibition centre and car park in the quarry floor and installing a lift to carry visitors up from the octagon to the dome.
The museum opened in May 1997. The main exhibition area is housed beneath the dome and focuses on three main issues: the story of the V-weapons; life in occupied France; and the conquest of space after the war. It presents audio-visual displays in English, French, Dutch and German as well as a large number of original artifacts including a V-1 provided by the Science Museum
in London
and a V-2 provided by the Smithsonian Institution
in Washington, D.C.
In 2011, the museum welcomed 120,000 visitors. Since 2010, the museum has also managed the V-3
site of the Fortress of Mimoyecques.
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
between 1943 and 1944 to serve as a launch base for V-2 rocket
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...
s against London and southern England. It is situated in the commune
Communes of France
The commune is the lowest level of administrative division in the French Republic. French communes are roughly equivalent to incorporated municipalities or villages in the United States or Gemeinden in Germany...
of Helfaut
Helfaut
Helfaut is a commune in the Pas-de-Calais department in the Nord-Pas-de-Calais region of France.-Geography:A large village situated 4 miles south of Saint-Omer, at the D195 and D198 crossroads....
in the Pas-de-Calais region of northern France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
, about 5 kilometres (3.1 mi) from Saint-Omer
Saint-Omer
Saint-Omer , a commune and sub-prefecture of the Pas-de-Calais department west-northwest of Lille on the railway to Calais. The town is named after Saint Audomar, who brought Christianity to the area....
.
Constructed in the side of a disused chalk quarry, the complex comprised an immense concrete dome, to which its modern name refers, above a network of tunnels that were to house the launch facilities and crew quarters. The facility was intended to store a large stockpile of V-2s, warheads and fuel and to be able to launch missiles against London and southern England at a high daily rate. Heavy secret weapons sites like Wizernes, Watten, Mimoyecques and the Wasserwerks of St Pol, Desvres, were collectively called by the Organization Todt the "Special Constructions", in German.
However, due to repeated heavy bombing by Allied forces carried out as part of Operation Crossbow
Operation Crossbow
Crossbow was the code name of the World War II campaign of Anglo-American "operations against all phases of the German long-range weapons programme—operations against research and development of the weapons, their manufacture, transportation and their launching sites, and against missiles in flight"...
, the Germans were unable to complete the construction works and the complex never entered service. It was captured by the Canadian Army in September 1944 and was subsequently abandoned. The complex remained derelict and abandoned until the mid-1990s. In 1997 it opened to the public for the first time after being redeveloped into a museum. The tunnels and the main exhibition area under the dome tell the story of the German occupation of France during World War II, the V-weapons and the history of space exploration
Space exploration
Space exploration is the use of space technology to explore outer space. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft....
.
Background
The deployment of the V-2 missile required large quantities of liquid oxygenLiquid oxygen
Liquid oxygen — abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries — is one of the physical forms of elemental oxygen.-Physical properties:...
(LOX) – more, in fact, than was available from existing production sites in Germany and the occupied countries. New sources of LOX were required, situated close to the missile launching sites to reduce as far as possible the loss of propellant through evaporation. The missile's operational range of 320 kilometres (198.8 mi) meant that the launch sites had to be located fairly close to the English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...
or southern North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
coasts, in northern France, Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...
or the western Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
.
Because of the complexity of the missile and the need for extensive testing prior to launch, the V-2's designers at the Peenemünde Army Research Center favoured using heavily defended fixed sites where the missiles could be stored, armed, fueled from an on-site LOX production plant and launched. This was opposed by the German Army and the V-2 project's head, Major-General Walter Dornberger
Walter Dornberger
Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....
, who were concerned that the sites would be vulnerable to aerial attack by the Allies. The Army's preferred option was to use Meillerwagen
Meillerwagen
The Meillerwagen was a German World War II trailer used to transport a V-2 rocket from the 'transloading point' of the Technical Troop Area to the 'launching point', to erect the missile on the Brennstand , and to act as the service gantry for fuelling and launch preparation...
s, mobile firing batteries, which presented a much smaller target for the Allied air forces.
The Army was nonetheless overruled in March 1943 by Adolf Hitler
Adolf Hitler
Adolf Hitler was an Austrian-born German politician and the leader of the National Socialist German Workers Party , commonly referred to as the Nazi Party). He was Chancellor of Germany from 1933 to 1945, and head of state from 1934 to 1945...
. His long-standing preference for huge, grandiose constructions led him to order the construction of a massive bunker (now known as the Blockhaus d'Éperlecques) in the Forest of Éperlecques
Forest of Éperlecques
The Forest of Éperlecques is a large forest covering some 850 hectares in the commune of Éperlecques in the Pas-de-Calais department in the Nord-Pas-de-Calais region of France. Trails through the forest provide leisure opportunities for walkers...
near Watten
Watten, Nord
-Sights:The village is famous for its old ruined abbey, and for its mill, which was restored in the 1990s. These two buildings are located on the "Mountain of Watten" . Its church dates from the thirteenth century.-References:* *...
, north of Saint-Omer. The bunker was soon spotted by Allied reconnaissance and on 27 August 1943, a raid by 187 B-17 bombers wrecked the site before it could be completed. A surviving portion was re-used by the Germans as a LOX production facility.
Design and location
The successful attack against the Watten bunker forced the Germans to find an alternative location for a launch site nearby. An old quarry situated between the villages of Helfaut and WizernesWizernes
Wizernes is a northern French commune southwest of Saint-Omer on the banks of the river Aa at the D928 and D211 road junction. The commune is subdivided into townships. and is twinned with Ensdorf, Saarland, Germany.-History:...
, south-west of Saint-Omer some 12 kilometres (7.5 mi) south of the Watten bunker, had already been designated for use to store missiles in tunnels bored into the chalk hillside. It was located near the Aa river
Aa River (France)
The Aa is an 89 km long river in northern France. Its source is near the village Bourthes. It flows through the following départements and cities:* Pas-de-Calais: Saint-Omer.* Nord: Gravelines....
alongside the Boulogne–Saint-Omer railway line, about three-quarters of a mile (1 km) from Wizernes station. The Germans had already undertaken major work in August 1943 to lay extensive railway sidings to connect the quarry to the main line.
On 30 September 1943, Hitler met with Albert Speer
Albert Speer
Albert Speer, born Berthold Konrad Hermann Albert Speer, was a German architect who was, for a part of World War II, Minister of Armaments and War Production for the Third Reich. Speer was Adolf Hitler's chief architect before assuming ministerial office...
, the Minister of Armaments and War Production, and Franz Xaver Dorsch
Franz Xaver Dorsch
Franz Xaver Dorsch was a German civil engineer who became the chief engineer of the Organisation Todt , a civil and military engineering group in Nazi Germany that was responsible for a huge range of engineering projects at home and in the territories occupied by the Germans during the Second...
, the chief engineer of the Todt Organisation, to discuss plans for a replacement for the out-of-commission Watten facility. Dorsch proposed to transform the Wizernes depot into a vast bomb-proof underground complex that would require a million tons of concrete to build. It would be constructed within a network of tunnels to be dug inside the hillside at the edge of the quarry. A concrete dome, 5 feet (1.5 m) thick, 71 metres (232.9 ft) in diameter and weighing 55,000 tons, would be built over the top of the central part of the facility to protect it from Allied bombing. Beneath it, about 7 kilometres (4.3 mi) of tunnels were to be dug into the chalk hillside to accommodate workshops, storerooms, fuel supplies, a LOX manufacturing plant, generators, barracks and a hospital.
A standard gauge railway tunnel, codenamed Ida, was to be built on a curving path that would connect it with both the east- and west-bound main line railway, allowing trains to run straight through the complex without needing to reverse or be turned around. This would serve as the main unloading station, where missiles and supplies would be offloaded onto trolleys that would transport them into the connecting galleries Mathilde and Hugo. Hugo connected in turn with Sophie, a dead-end railway tunnel branching from the main line into Ida. Each of the main tunnels had a number of unnamed side tunnels of the same dimensions as the main tunnels and up to 90 metres (295.3 ft) long. The central feature of the complex was a huge octagonal chamber directly under the dome. It was never completed but would have been 41 metres (134.5 ft) in diameter and up to 33 metres (108.3 ft) high. A number of intermediate floors, possibly as many as ten, would have been built up the sides of the chamber.
The western side of the chamber opened onto two tall passageways called Gustav and Gretchen. Each was to have been protected by bomb-proof doors made of steel and concrete. The passageways were to be 4 metres (13.1 ft) wide and at least 17 metres (55.8 ft) high and were angled in a Y-shape, exiting into the quarry. Open-air platforms for launching rockets would have been situated at the end of each passageway. The two passageways were angled at 64° 50' and 99° 50' west of north respectively – not aligned with any probable target but merely permitting the rockets to be transported to sufficiently widely separated launch pads.
The facility was designed, as was its predecessor at Watten, to receive, process and launch V-2 rockets at a high rate. Trains carrying V-2s would enter the heart of the complex through the Ida rail tunnel, where they would be unloaded. A large number of V-2s could be stored in the side tunnels; LOX would also be produced on-site ready for use. When the time came, the rockets would be moved into the octagonal preparation chamber where they would be lifted to a vertical position for fueling and arming. From there they would be transported on motorised launch carriages through the Gustav and Gretchen passageways and out to the launch pads, ready to be fired.
The priority target for the V-2s was London, 188 kilometres (116.8 mi) away, that Hitler wanted to see pulverised by the end of 1943. The Allies were alarmed when a photo interpreter found out that part of the complex was aligned within half a degree of the Great Circle
Great circle
A great circle, also known as a Riemannian circle, of a sphere is the intersection of the sphere and a plane which passes through the center point of the sphere, as opposed to a general circle of a sphere where the plane is not required to pass through the center...
bearing on New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...
, though Albert Speer denied after the war that there had been any intention of using Wizernes as a launch site for intercontinental missiles such as the planned A10.
Although physically separate, another facility built in nearby Roquetoire
Roquetoire
Roquetoire is a commune in the Pas-de-Calais department in the Nord-Pas-de-Calais region of France.-Geography:Roquetoire is located some 7 miles southeast of Saint-Omer at the junction of the D195 and the D187 roads.-Population:...
was an integral part of the Wizernes complex. Umspannwerk C was built to house a Leitstrahl radio command guidance system which could be used to send course corrections to missiles launched from Wizernes to fine-tune their trajectory during the launch phase.
Construction
After the WattenWatten
-Places:Scotland* Watten, Highland, a village in Caithness, in the Highland local government area of ScotlandFrance* Watten, Nord, a commune in the Nord département of France...
bunker had been put out of commission, Hitler agreed to convert the Wizernes storage bunker to a launching site. in October 1943, Speer noted that "he [the Führer] is not convinced that the site will ever be finished". Construction work began in October 1943 and the building of the dome commenced in November. It proved a slow process because of constant air-raid warnings, which stopped work 229 times in May 1944 alone. The constant delays were a source of major frustration as they meant that the Todt Organisation could not provide a completion date. Dornberger's representative commented: "This means that no date can be set for the specialised launching gear and machinery to be installed. General Dornberger has asked Field Marshal
Field Marshal
Field Marshal is a military rank. Traditionally, it is the highest military rank in an army.-Etymology:The origin of the rank of field marshal dates to the early Middle Ages, originally meaning the keeper of the king's horses , from the time of the early Frankish kings.-Usage and hierarchical...
von Rundstedt
Gerd von Rundstedt
Karl Rudolf Gerd von Rundstedt was a Generalfeldmarschall of the German Army during World War II. He held some of the highest field commands in all phases of the war....
to decide whether it would not be better to abandon the whole project."
Dornberger reported that he considered the structure to be useless. However, this was contradicted by Todt engineers and fortification experts, and by Hitler himself, whom Speer recorded was "infuriated by this frivolous way of reporting things." In response to Hitler's desire to see the site completed the workforce was built up substantially from 1,100 in April 1944 to nearly 1,400 by June. About 60% of the workers were Germans; skilled workers, such as miners from Westphalia
Westphalia
Westphalia is a region in Germany, centred on the cities of Arnsberg, Bielefeld, Dortmund, Minden and Münster.Westphalia is roughly the region between the rivers Rhine and Weser, located north and south of the Ruhr River. No exact definition of borders can be given, because the name "Westphalia"...
, were recruited to excavate the tunnels and build the dome. The remainder were principally Frenchmen conscripted by the Service du travail obligatoire
Service du travail obligatoire
The Service du travail obligatoire was the forced enlistment and deportation of hundreds of thousands of French workers to Nazi Germany in order to work as forced labour for the German war effort during World War II....
(STO), plus Soviet prisoners of war. The project was overseen by several large German construction companies, with Philip Holzman A.G. of Frankfurt am Main and the Grossdeutsche Schachtbau and Tierbohr GmbH serving as the chief contractors.
One of the most difficult challenges faced by the Germans was that of how to construct the great dome while under regular air attack. The dome's designer, Todt Organisation engineer Werner Flos, hit upon the idea of building the dome first, flat upon the ground, and then excavating the soil underneath it so that the construction works below would be protected against aerial attacks. A circular trench was excavated on the top of the hill above the quarry to an outside diameter of 84 metres (275.6 ft). The dome was built within this trench and the galleries and octagonal preparation chamber were excavated below.
As an additional bomb-proofing method, the dome was surrounded by a bomb-proof "skirt" or Zerschellerplatte of steel-reinforced concrete, 14 metres (45.9 ft) wide and 2 metres (6.6 ft) thick. This was supported by a series of buttresses, which were not tied into the dome itself, above the entrances to the Gustav and Gretchen tunnels. Another concrete structure was tied into the skirt to the northwest of the dome, which was perhaps intended for use as an observation and control tower. A separate underground building was constructed on the western side of the quarry to serve as a hospital and as offices for the engineers. A Decauville
Decauville
The Decauville manufacturing company was founded by Paul Decauville , a French pioneer in industrial railways. Decauville's major innovation was the use of ready-made sections of light, narrow gauge track fastened to steel sleepers; this track was portable and could be disassembled and transported...
narrow-gauge railway was installed on the quarry floor to transport supplies from the main line to the construction site.
A cube-shaped concrete building was constructed on the top of the hill, next to the dome. This was intended to be used as the bomb-proof outlet for a ventilation and air conditioning shaft – an essential element for a facility where dangerous and explosive gases were expected to be used in large quantities on a daily basis. It was never finished and when the Allies captured the site they found that the ventilation shaft had not been fully excavated. The building survived the bombing intact and is still prominently visible today.
Unlike its sister site at Watten, there was no on-site power plant; electricity at Wizernes was provided by a connection to the main electric grid, with consumption estimated at between 5,000–6,000 kVA
Volt-ampere
A volt-ampere is the unit used for the apparent power in an electrical circuit, equal to the product of root-mean-square voltage and RMS current. In direct current circuits, this product is equal to the real power in watts...
.
Discovery and Allied attacks
The Allies became aware of the Wizernes site in August 1943 when the Germans began laying extensive new rail sidings which were spotted by RAF reconnaissance flights. In November 1943, the Allied Central Interpretation UnitRAF Medmenham
RAF Medmenham was a Royal Air Force station based at Danesfield House near Medmenham, in Buckinghamshire, England.Activities there specialized in photographic intelligence, and it was once the home of the RAF Intelligence Branch...
reported that the Germans had begun constructing the concrete dome and were undertaking tunnelling works in the east face of the quarry. However, it was not until the following March that the Allies added the site to the list of targets for Operation Crossbow
Operation Crossbow
Crossbow was the code name of the World War II campaign of Anglo-American "operations against all phases of the German long-range weapons programme—operations against research and development of the weapons, their manufacture, transportation and their launching sites, and against missiles in flight"...
, the ongoing bombing campaign against V-weapon sites that had already wrecked the Watten bunker and numerous V-1 launching sites. Over the next few months, the USAAF and RAF carried out 16 air raids involving 811 bombers that dropped some 4,260 tons of bombs. The bombings caused destruction across a wide area, killing 55 residents of the nearby village of Helfault.
Conventional bombing raids only achieved a single bomb hit the dome itself, causing negligible damage. However, in June and July 1944 the RAF began attacking the site with 6-ton ground-penetrating Tallboy bombs. The external construction works were completely wrecked by the bombing and one Tallboy landed just beside the dome, blowing out the entire quarry cliff face and burying the entrances to the Gustav and Gretchen tunnels. The entrance to Sophie was also buried, leaving Ida as the only entrance to the facility. The dome was unscathed but the buttresses supporting the protective Zerschellerplatte were dislodged and slid partway down into the quarry. Serious damage was also caused to the tunnels beneath the dome. The damage made it impossible to continue work on the site. Dornberger complained: "Persistent air attack with heavy and super-heavy bombs so battered the rock all around that in the spring of 1944 landslides made further work impossible." His staff reported on 28 July 1944 that, although not hit by the Tallboys, "the whole area around has been so churned up that it is unapproachable, and the bunker is jeopardised from underneath."
In May 1944, the 953 (Semi-Mobile) Artillery Detachment started Abteilungen (firing detachment) training at Blizna
Blizna
Blizna is a village in the administrative district of Gmina Ostrów, within Ropczyce-Sędziszów County, Subcarpathian Voivodeship, in south-eastern Poland. It lies approximately north of Ostrów, north of Ropczyce, and north-west of the regional capital Rzeszów...
in southeastern Poland for operations at Wizernes. Consisting of one technical and two operational batteries, the detachment was expected to launch up to 50 rockets daily from Wizernes. However, they never got the chance. On 3 July 1944, the Oberkommando West
Oberkommando der Wehrmacht
The Oberkommando der Wehrmacht was part of the command structure of the armed forces of Nazi Germany during World War II.- Genesis :...
gave permission to stop construction at the heavily damaged Watten and Wizernes sites. On 18 July 1944, Hitler abandoned plans for launching V-2s from bunkers and authorized the downsizing of the Wizernes bunker into a LOX production facility. However, these plans were overtaken by the liberation of Northern France consecutive to the Normandy landings. The site was finally abandoned and inspected by British engineers on 5 September.
Post war investigations
Shortly after the Wizernes site had been captured in September 1944, Duncan SandysDuncan Sandys
Edwin Duncan Sandys, Baron Duncan-Sandys CH PC was a British politician and a minister in successive Conservative governments in the 1950s and 1960s...
, the head of the British "Crossbow Committee" investigating the V-weapons programme, ordered the constitution of a Technical Inter-Services Mission under Colonel T.R.B. Sanders
Terence Sanders
Terence Robert Beaumont Sanders was a British rower who competed in the 1924 Summer Olympics, a lecturer in engineering at Cambridge, an army officer engaged in countering the V2 threat, civil servant and High Sheriff of Surrey.Sanders was born in Charleville, Cork, Ireland. He was educated at...
. It was given the task of investigating the sites at Mimoyecques, Siracourt, Watten, and Wizernes, collectively known to the Allies as the "Heavy Crossbow" sites. Sanders' report was submitted to the War Cabinet on 19 March 1945.
The purpose of the Wizernes site had been unclear prior to its capture but Sanders was able to deduce its connection with the V-2 from the dimensions of the complex and some intelligence information that his team had been able to retrieve. Sander's report concluded that it was "an assembly site for long projectiles most conveniently handled and prepared in a vertical position". He conjectured the approximate length of the projectiles from the height of the Gustav and Gretchen tunnels, though he noted that there was some doubt about the height of the doors at the tunnel entrances. Segments of the doors had been recovered from a storage dump near Watten railway station, but were incomplete. The maximum size of the projectile could thus have been between 17 metres (55.8 ft) and 24 metres (78.7 ft) in length and 4 metres (13.1 ft) in breadth. (This was substantially larger than the V-2, which measured 14 metres (45.9 ft) long and 3.55 metres (11.6 ft) wide.) Two witnesses interviewed by the Sanders team reported "an intention of firing a projectile 18 metres long." Sanders noted that "the dimensions of the site make it suitable for the A.4 (V-2
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...
) rocket, but the possibility of a new rocket up to half as long again as the A.4 and twice the weight cannot be ruled out."Although the V-2 rocket
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range combat-ballistic missile and first known...
at 14 metres (45.9 ft) long could have been carried by a car through the Sanders-identified height , the Aggregate series#A10 A10 New York rocket design was too tall--even without a rail carrier--at 26 m (85.3 ft). He concluded that much of the site was becoming unsafe due to the progressive collapse of timbering and recommended that the tunnels and workings under the dome should be destroyed to prevent subsequent accidents or misuse.
The site reverted to private ownership after the war. As the quarry had long since been worked out, it was abandoned. The tunnels were not destroyed but were sealed off, though at some point they were reopened by local people and could be entered; the octagon remained sealed off with a ceiling-to-floor barricade. The quarry itself remained in almost the same condition as it had been in 1944, with sections of railway track still in place on the quarry floor. The hospital section remained relatively intact and was used by the local gendarmes as a shooting range.
Museum of La Coupole
In 1986, the Espace Naturel Régional in LilleLille
Lille is a city in northern France . It is the principal city of the Lille Métropole, the fourth-largest metropolitan area in the country behind those of Paris, Lyon and Marseille. Lille is situated on the Deûle River, near France's border with Belgium...
earmarked 10 million FF
French franc
The franc was a currency of France. Along with the Spanish peseta, it was also a de facto currency used in Andorra . Between 1360 and 1641, it was the name of coins worth 1 livre tournois and it remained in common parlance as a term for this amount of money...
to develop the site as a tourist attraction for the Nord-Pas-de-Calais region with the intention of establishing a Second World War museum there. The plan was publicised in a special open weekend on 20/21 June 1987, attended by over 20,000 people, in which the dome's designer Werner Flos met Professor Reginald Victor Jones
Reginald Victor Jones
Reginald Victor Jones, CH CB CBE FRS, was a British physicist and scientific military intelligence expert who played an important role in the defence of Britain in -Education:...
, a surviving member of the "Crossbow Committee", at Wizernes. The Ida tunnel and side chambers were opened to the public and used for an audio-visual exhibition of the site's history.
Local historian Yves le Maner was charged with the task of developing the project while a feasibility study was conducted into the possibility of completing some of the original excavation work to make the site safe for public access. The plans were approved in 1993 and the site was bought by the Commune de Helfaut. The following year, the Conseil Général du Pas-de-Calais acquired the site. The 69 million FF project (£7.5 million at 1997 prices) was largely underwritten by the Conseil Général, which provided 35 million FF, with another 17 million FF coming from the regional council. The European Community provided a further 12 million, the French State provided 3 million FF and the Saint-Omer municipal administration funded the remaining 1 million FF; a number of private shareholders were also involved. The Societé d'Equipement du Pas-de-Calais was contracted to carry out the development work, which involved excavating a further two metres (six feet) beneath the dome, clearing out and completing the unfinished concreting of some of the tunnels, building an exhibition centre and car park in the quarry floor and installing a lift to carry visitors up from the octagon to the dome.
The museum opened in May 1997. The main exhibition area is housed beneath the dome and focuses on three main issues: the story of the V-weapons; life in occupied France; and the conquest of space after the war. It presents audio-visual displays in English, French, Dutch and German as well as a large number of original artifacts including a V-1 provided by the Science Museum
Science Museum (London)
The Science Museum is one of the three major museums on Exhibition Road, South Kensington, London in the Royal Borough of Kensington and Chelsea. It is part of the National Museum of Science and Industry. The museum is a major London tourist attraction....
in London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
and a V-2 provided by the Smithsonian Institution
Smithsonian Institution
The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...
in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
In 2011, the museum welcomed 120,000 visitors. Since 2010, the museum has also managed the V-3
V-3 cannon
The V-3 was a German World War II supergun working on the multi-charge principle whereby secondary propellant charges are fired to add velocity to a projectile....
site of the Fortress of Mimoyecques.
Air raids on the Wizernes site
| Date | |
|---|---|
| 11 March 1944 |  34 of 51 B-24 LiberatorB-24 Liberator The Consolidated B-24 Liberator was an American heavy bomber, designed by Consolidated Aircraft of San Diego, California. It was known within the company as the Model 32, and a small number of early models were sold under the name LB-30, for Land Bomber... s of the 2d Bombardment Division's 44th and 93d Heavy Bombardment groups attacked Wizernes using blind-bombing techniques due to thick overcast, dropping 127 tons of bombs. |
| 19 March 1944 | 152 B-26 Marauder B-26 Marauder The Martin B-26 Marauder was a World War II twin-engine medium bomber built by the Glenn L. Martin Company. First used in the Pacific Theater in early 1942, it was also used in the Mediterranean Theater and in Western Europe.... s of IX Bomber Command attacked V-weapon sites around Saint-Omer. |
| 26 March 1944 | 500 heavy bombers of the 8th Air Force attacked a total of 16 V-weapon sites in northern France, including Wizernes, dropping 1,271 tons of bombs. Allied losses were four B-17s and one B-24; a further 236 bombers were damaged by enemy fire. |
| 17 April 1944 | 14 B-24s and five pathfinder aircraft used an experimental bombing technique to attack Wizernes. |
| 25 April 1944 | 27 B-24s from 2d Bombardment Division bombed Wizernes in a special test of new pathfinding equipment. |
| 3 May 1944 | 47 B-24s escorted by 101 fighters from VIII Fighter Command attacked Wizernes using blind-bombing techniques. |
| 20 June 1944 |  17 Lancasters and 3 MosquitosDe Havilland Mosquito The de Havilland DH.98 Mosquito was a British multi-role combat aircraft that served during the Second World War and the postwar era. It was known affectionately as the "Mossie" to its crews and was also nicknamed "The Wooden Wonder"... of No 617 Squadron attempted to attack Wizernes but were forced to abort by cloud cover over the target. |
| 22 June 1944 | A second 617 Squadron attack on Wizernes was again thwarted by cloud cover. |
| 24 June 1944 | 617 Squadron returned to Wizernes with 16 Lancasters and 2 Mosquitos, losing one Lancaster to anti-aircraft fire. Several Tallboy bombs were dropped but failed to cause much damage. |
| 28 June 1944 | 103 Halifaxes Handley Page Halifax The Handley Page Halifax was one of the British front-line, four-engined heavy bombers of the Royal Air Force during the Second World War. A contemporary of the famous Avro Lancaster, the Halifax remained in service until the end of the war, performing a variety of duties in addition to bombing... and 5 Mosquitos from No. 4 Group No. 4 Group RAF No. 4 Group was a Royal Air Force group, originally formed in World War I, and reformed in the wake of the Second World War, mostly part of RAF Bomber Command, but ending its days in RAF Transport Command.-Formation in World War I:... and 2 Lancasters of the Pathfinder Force attacked Wizernes without loss. |
| 17 July 1944 | 72 Halifaxes, 28 Stirlings Short Stirling The Short Stirling was the first four-engined British heavy bomber of the Second World War. The Stirling was designed and built by Short Brothers to an Air Ministry specification from 1936, and entered service in 1941... , 20 Lancasters, 11 Mosquitos and 1 Mustang attacked three V-weapons sites including Wizernes, which was attacked with a dozen Tallboys. The attack caused severe damage to the site and buried the entrances to the launch tunnels Gustav and Gretchen. The site was abandoned a few weeks later. |
| 20 July 1944 | 174 Lancasters, 165 Halifaxes and 30 Mosquitos attacked V-1 launching sites and the Wizernes site. |
| 20/21 July 1944 | 54 Halifaxes, 23 Lancasters and 10 Mosquitos attacked V-weapon sites at Ardouval Ardouval Ardouval is a commune in the Seine-Maritime department in the Haute-Normandie region in northern France.-Geography:A small farming and forestry village in the Pays de Bray, situated some southeast of Dieppe, at the junction of the D212 and D915 roads.... and Wizernes, but no bombs were dropped at Wizernes due to bad weather. |
| 4 August 1944 | An experimental Operation Aphrodite Operation Aphrodite Aphrodite and Anvil were the World War II code names of United States Army Air Forces and United States Navy operations to use B-17 and PB4Y bombers as precision-guided munitions against bunkers such as those of Operation Crossbow.... attack using remotely-controlled B-17s packed with explosives failed when the drone aircraft overshot Wizernes by 2,000 feet. |