'Hadrian' was a British unrealised plan for a combined operations attack to retake the German-occupied Channel Islands and at the same time to seize Cherbourg, a major port on the north coast of the Cotentin peninsula in the German-occupied northern part of France (summer 1943).

The plan proceeded no further than the concept stage as the amphibious capability which its implementation would have required was earmarked the 'Husky' (i) assault on Sicily.