Even though this happened within my lifetime, I don't think I've heard of this before:
Britain's 'big bang' in Heligoland, 70 years on
By Kevin Connolly BBC News, Heligoland
Video: 1m 30s.
Brexit may have triggered a political earthquake in Europe, but 70 years ago the UK sent real shockwaves across the seas with the largest non-nuclear explosion of that era.
As one of the four victorious allied powers after World War Two, Britain was governing a large area of occupied Germany.
The British sector included the tiny island of Heligoland, which had long been a source of diplomatic tension between the two countries.
So, when in 1947 the British needed a safe place to dispose of thousands of tonnes of unexploded ammunition, Heligoland must have seemed an obvious choice.
The code-name for the plan combined the British flair for understatement with the military taste for the literal-minded; it was to be called Operation Big Bang.
Heligoland had been a German naval fortress, and historian Jan Rueger, author of Britain, Germany, and the Struggle for the North Sea, says Operation Big Bang was designed by the British to make a big point.
"They're very clear that there's a symbolic side to this [operation] and that is the German tradition of militarism," he explains.
"There's a sense that Prussian militarism and its threat to Britain has to end and that's very much how Operation Big Bang is received in Britain."
The operation was carefully stage-managed - the old black and white pictures even include a close-up of a Royal Navy officer's finger triggering the blast. Aerial footage shows the entire horizon erupting in a huge grey curtain of mud, sand and rock.
For the Royal Navy and the British Army of Occupation it was mission accomplished.
For the people of Heligoland it felt very different.
Europe in 1946 and 1947 was in chaos, with millions of displaced and dispossessed families drifting between camps or sheltering in ruined buildings.
The island had been evacuated during the war and many Heligolanders were living in exile in the coastal city of Cuxhaven about 60km (37 miles) to the south.
Olaf Ohlsen, who was 11 years old in 1947, gathered with the rest of the exiled population on the cliffs to listen for the sound of the explosion.
Few people in history can have lived through such a moment, standing at the edge of sea knowing that they would hear but not see an explosion that they knew would destroy their homes.
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http://www.bbc.co.uk/news/world-europe-39590752