Cockatoo Island Military Guard Room

Cockatoo Island became a jail in 1839, following advice by New South Wales Governor George Gipps to the British Secretary of State for the Colonies that convicts would be sent to the island after the closure of the Norfolk Island convict establishment. The convict precinct (see also Cockatoo Island Prison Barracks Precinct, 1951, 1953 and 1859) was built over the next few years, the buildings beginning to be occupied from October 1841. Quarrying of grain silos (Biloela House and Underground Grain Silos) was one of the early convict tasks. In order to service Royal Navy ships, the Fitzroy Dock was built on the island and completed in 1857. Cockatoo became the major government dockyard in Australia.^[1]

In 1869 prisoners were transferred from the island to Darlinghurst, and the prison buildings became an industrial school for girls and a reformatory in 1871. The dockyard area was now separated from this institutional area on the top of the island by a fence. Following the departure of the girls in 1888, prisoners were again sent to the island, and the jail function continued until about 1909. Meanwhile, the dockyard function expanded, and the Sutherland Dock was built in 1890. The NSW Public Works Department declared Cockatoo the state dockyard.^[1]

After Federation, in 1913 Cockatoo became the Commonwealth Dockyard, and the island, both through shipbuilding and servicing, played an important role both in the development of the Royal Australian Navy and during the First World War. The former prison buildings were now used for office purposes. From 1933 the dockyard was leased from the Australian Government by Cockatoo Docks and Engineering Co Ltd and the island played a very significant role during the Second World War. After the war, now known as Vickers, the dockyard continued, and submarine facilities were introduced. The dockyard closed in 1992, and there was some demolition. Sale of the island was proposed. The island is now vested in the Sydney Harbour Federation Trust.^[1]

The military guard room, with detached kitchen and toilet, was erected in 1842, and a cell block (later demolished) was completed three years later. The buildings were designed by the Commanding Royal Engineer, Colonel George Barney, who played a notable role in the colony. During the female institution phase, the guard room was used as a sewing room, then as a store and office. After the females' departure, the room became offices and accommodation for the resident engineer, before a new wing was added and the building reverted to prison purposes. After Commonwealth assumption of control, the room was used as a residence by the 1920s. After the Second World War the buildings' roofs were removed; stone was also cannibalised for use elsewhere on the island. In 1980 parts of the room were removed and the walls were topped with cement render.^[1]

The guard room and the other convict-era buildings form the only remaining imperial-funded (as opposed to colonial) convict public works complex in New South Wales and form one of the most complete groups of convict structures in Australia.^[1]