The force which descended on Cuba consisted of 22 ships of the line, four 50-gun ships, three 40s, a dozen frigates and a dozen sloops and bomb vessels. In addition there were troopships, storeships, and hospital ships. Pocock took this great fleet of about 180 sail through the dangerous Old Bahama Strait, from Jamaica, to take Havana by surprise. Havana, on Cuba's north coast, was guarded by the elevated Morro Castle which commanded both the entrance to its fine harbour, immediately to the west, and the town on the west side of the bay. The English fleet moved into Havana harbour once the obstructions had been cleared on 21 August.

On the left of the picture, Commodore Augustus Keppel in the 'Valiant', is leading in his squadron first, an honour accorded him by Admiral Sir George Pocock. On the right Pocock's 'Namur', flying his flag as Admiral of the Blue, together with the Union flag and blue ensign, is shown following with the bulk of the fleet.