Operation Crossbow - Heavy Sites - Wizernes

The 'Heavy Sites' were the large bomb proof installations in northern France associated with the German V Weapon programme.
 
Wizernes was developed by the Germans following the first attack on Watten, in August 1943, as an alternative site for the bomb-proof launching of V2 rockets. Construction work began in November 1943 on a million ton concrete dome that was located on the hillside beside a quarry with a vast tunnel network developed in the hillside. It was planned that rocket parts would be delivered to the site by rail, where they would be safely assembled inside the hill and under the massive concrete dome. The Allies used conventional bombs to attack the site from March 1944, whilst it was still under construction.
 
On 17 July 1944 the site was attacked in a raid led by Group Captain Leonard Cheshire, when Tallboy bombs managed to create an earthquake effect that undermined the dome and forced the Germans to abandon the site.
 
In 1997, the site was re-opened as the La Coupole history and science museum.