Secret German WWII Rocket Complex

La Coupole (English: The Dome) was a Nazi Germany bunker constructed in a former limestone quarry and planned for V-2 rocket assembly and launches. The site was bombed as a "Heavy Crossbow" target and the rockets were launched from mobile firing batteries, instead.

In January 1944 a concrete dome 71 m in diameter, 5 m thick and weighing an estimated 55 000 tonnes was built over the top of the facility. Similar to the Verbunkerung method, the Wizernes plan was to build a bomb-proof dome on the ground on the edge of the 30 m / 100-foot-deep quarry, then excavate a facility beneath. Directly beneath the dome, a 35 m / 117 ft diameter-by-21 m high hexagonal room was planned to house the rocket production facility. After final assembly and fueling, the rockets were to be moved outside and fired.