In late October 1918 the British Grand Fleet, based at Rosyth in the Firth of Forth, had 35 dreadnought battleships and 11 battlecruisers (including two of the very lightly armoured Courageous class). Twenty of these ships had been completed since the outbreak of war, and a third of them were armed with the highly effective 15-inch gun; the oldest capital ship in the fleet was Indomitable (commissioned in June 1908) while HMS Dreadnought was put in reserve in July 1918. Five of these ships were from the United States Navy and one from the Royal Australian Navy.