La Coupole - Discovery and Allied Attacks

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 Unit 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 bombing caused destruction across a wide area, killing 55 residents of the nearby village of Helfault.

Conventional bombing raids only achieved a single bomb hit on the dome itself, causing negligible damage. However, in June and July 1944 the RAF began attacking the site with 12,000 lb (5,443 kg) 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 the dome had not been hit by the Tallboys, "the whole area around has been so churned up that it is unapproachable, and the bunker is jeopardised from underneath."

Although three launch battalions were formed by the Germans in late 1943, they never got the chance to deploy to the V-weapons launch sites at Watten and Wizernes. On 3 July 1944, the Oberkommando West authorised the cessation of construction at the heavily damaged sites. On 18 July 1944, Hitler abandoned plans for launching V-2s from bunkers and authorized the downgrading of the Wizernes bunker to make it a LOX production facility. However, these plans were overtaken by the Allied liberation of Northern France following the Normandy landings. The site was finally abandoned a few days before the Allies reached it at the start of September during the rapid liberation of the area by British, American, Canadian and Polish troops. British engineers inspected it on 5 September.