12. The Allies Spotted the Super Gun’s Construction But Did Not Know What it Was. Luckily for London, they Destroyed it Anyhow
The Allies were completely in the dark about the V-3 Cannon program. Aerial reconnaissance flights did spot the strange new construction activity surrounding the Pas de Calais complex. However, analysts assumed that the photos depicted a potential launching base for the V-2 rockets. V-2s were worrisome in of themselves, so the site was subjected to frequent Allied bombing starting from late 1943 onwards. The raids seriously disrupted construction and forced the Germans to abandon parts of the V-3 Cannon complex.
The remainder of the site was seriously damaged in July 1944, in a raid that used heavy ground-penetrating bombs, which burrowed deep beneath the surface before detonating. The underground explosions wrecked and collapsed the tunnel system, and buried hundreds of workers and technicians. Construction was halted as the Allies advanced up the coast from Normandy to the Pas de Calais, and the abandoned V-3 complex fell to advancing Canadian troops in September 1944. It was only then that the Allies discovered just how big a threat the complex had actually posed, and just how lucky London had been to dodge that menace.
