A one million ton concrete dome constructed on the side of a chalk quarry with underground storage for the rockets, fuel supply, a liquid oxygen production facility, electricity generators and housing for the garrison. This is La Coupole, a massive remnant of World War II located five kilometers from Saint-Omer in France. La Coupole was built between 1943 and 1944 by Nazi German forces in France. It was meant to serve as a launch base for V-2 rockets directed against London and southern England, and is the earliest known precursor to modern underground…
