On this Date in 1947...

...in one of the largest non-nuclear single explosive detonations in history, the Royal Navy set off 6,800 tonnes of surplus ammunition in an unsuccessful attempt to destroy the island of Heligoland, Germany.  The head demolitions expert was overheard saying, "Huh, you woulda thought that should've worked."  To which his subordinate responded, "It's a friggin island, man.  Not a house."