Battle of Drøbak Sound

The Battle of Drøbak Sound took place in Drøbak Sound, the northernmost part of the outer Oslofjord in southern Norway, on 9 April 1940. It marked the end of the "Phoney War" and the beginning of World War II in Western Europe.

A German fleet led by the cruiser Blücher was dispatched up the Oslofjord to begin the German invasion of Norway, with the objective of seizing the Norwegian capital of Oslo and capturing King Haakon VII and his government. The fleet was engaged in the fjord by Oscarsborg Fortress, an ageing coastal installation near Drøbak, that had been relegated to training coastal artillery servicemen, leading the Germans to disregard its defensive value. However, unbeknownst to German military intelligence, the fortress' most powerful weapon was a torpedo battery, which would be used to great effect against the German invaders.

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