Battle of Anzio
The Battle of Anzio was an Allied amphibious assault in Italy during World War II. Held up by the German Gustav line south of Rome, they tried to circumvent it by landing further north along the west coast of Italy.
The Allied commanders were too slow to expand their beachhead, giving the Germans time to organize a potent counterattack that nearly drove them into the sea. The front lines then stabilized.
Churchill's assessment: "I had hoped that we were hurling a wildcat onto the shore, but all we got was a stranded whale."