'Castle' was a British unrealised special forces raid on a power station, which provided electricity to a nearby ilmenite mine, in the Jøssingfjord area of the south-western coast of German-occupied Norway (January 1941).

Scheduled for implementation on 17 January, the undertaking was to have used 250 commandos delivered to and later removed from the target area by destroyers. The operation was cancelled largely because of the opposition of Prime Minister Winston Churchill, who did not wish to let the Germans know, for so small a possible return, that the British had plans for special forces undertakings in Norway, for which he had altogether more grandiose ambitions.