The First World War memorial takes the form of a vaulted corridor, 21.5 metres long, 7 metres wide and 7 to 10 metres high. Inside are 12 bronze plaques engraved with 12,000 names. It was opened by Queen Mary on 12 December 1928. The Second World War memorial takes the form of a semi-circular sunken garden located behind the corridor, to its north. It contains the names of 24,000 British seamen and 50 Australian seamen, listed on the walls of the sunken garden. In the centre of the garden is a pool of bronze, engraved with a compass pointing north. The First World War memorial was designed by Edwin Lutyens and the Second World War memorial by Sir Edward Maufe