 On 13 October , the majority of the fleet conducted a sweep into the North Sea , returning to port on 15 October . During 2 – 5 November , Marlborough participated in a fleet training operation west of the <unk> . Another such cruise took place during 1 – 4 December . The typical routine of gunnery drills and squadron exercises occurred in January 1916 . The fleet departed for a cruise in the North Sea on 26 February ; Jellicoe had intended to use the Harwich Force to sweep the <unk> Bight , but bad weather prevented operations in the southern North Sea . As a result , the operation was confined to the northern end of the sea . On the night of 25 March , Iron Duke and the rest of the fleet sailed from Scapa Flow , to support the Battlecruiser Fleet and other light forces that raided the German <unk> base at <unk> . 
