La Coupole (), also known as the Coupole d'Helfaut-Wizernes and originally codenamed Bauvorhaben 21 (Building Project 21) or Schotterwerk Nordwest (Northwest Gravel Works), is a Second World War bunker complex in the Pas-de-Calais départment of northern France, about from Saint-Omer. It was built by the forces of Nazi Germany between 1943 and 1944 to serve as a launch base for V-2 rockets directed against London and southern England, and the earliest known precursor to modern underground missile silos still in existence.