New South Wales contains four convict sites. Cockatoo Island, set in Sydney Harbour, was used for dry dock building between 1839-69; the island was the site of one of Australia’s largest shipyards from 1870 to 1991, and is now a cultural heritage center offering public tours. The Great North Road, which links Sydney to the northern agricultural center of the Hunter Valley, was built by convict labor from 1825-36. Designed between 1818-19 by architect Francis Greenway, himself a former convict, Hyde Park Barracks in Sydney was used until 1848 as a home for convict men and boys employed by the Australian government; it is now open to the public. The oldest public building in Sydney (and actually set in the riverside suburb of Paramatta), the colonial-style Old Government House – the official residence of 10 early governors of New South Wales -- was built between 1815-22 using convict labour.