Photo: David Iliff
The Admiralty Extension, built in the late 19th century, is the largest of Admiralty buildings built to house the authority responsible for the command of the Royal Navy in the United Kingdom. Redesigned while under construction to accommodate the extra offices needed due to the naval arms race with the German Empire, it served as the headquarters of the Admiralty until 1964 when it was subsumed into the Ministry of Defence in nearby Whitehall.