Operation Big Bang

Operation Big Bang or British Bang was the explosive destruction of bunkers and other military installations on the island of Heligoland. The explosion used 7400 tons of surplus World War II ammunition, which was placed in various locations around the island and detonated at 1 p.m. on 18 April 1947 by the Royal Navy. The energy released was 13 terajoule, or about 3.2 kilotons of TNT equivalent making it the largest artificial non-nuclear explosion at that time. The objective of the blast was to destroy the bunkers and military installations on the North Sea island of Heligoland, but due to the enormous amount of explosives it was foreseen that the entire island might be destroyed. The porous sandstone that makes up the island allowed the blast wave to escape so only the southern tip of the island was destroyed, but there was considerable damage to the northern tip.