St Clair is a suburb of Sydney, in the state of New South Wales, Australia. It is 44 kilometres west of the Sydney central business district, in the local government area of the City of Penrith and is part of the Greater Western Sydney region. St Clair is within view of the Blue Mountains. History St Clair takes its name from a residential housing development established in 1970. The current St Clair Post Office opened on 17 March 1981. Aboriginal culture Traditionally, the area was inhabited by the indigenous Dharug people. By the year 1816 however, the Dharug people had been decimated by clashes with settlers and contracting diseases brought to the area by Europeans. As time passed, the traditional culture declined, as it did across the entire continent and they became increasingly dependent on the settlers for their survival. Although they had always maintained a camp on or around the Mamre estate (which is found adjacent to St Clair, in the suburb of St Marys, the Rev. Samuel Marsden now sought to encourage them to work in exchange for food and clothing. European settlement The area was part of an area named South Creek. It was later, unofficially, known as South St Marys, with the southern section being named Erskine Park. The original site of St Clair was once part of Chatsworth Nursery, a branch of Darling Nursery, which had been established in 1827 during the reign of King George IV. The owner Thomas Shepherd developed an irrigation system utilizing water from Eastern Creek and a large portion of the area was covered with Camelia orchards. The nursery, known for its camellias, was moved to Colyton and existed until the end of the 19th century. The area remained largely rural until a new housing development in the 1970s. The name "St Clair" has no historical links with the area. It was the name given to a residential housing development established in 1970 by the Latex Finance Company, a subsidiary of the Cambridge Finance Company which went bankrupt in the year 1976. The Land Commission of New South Wales acquired the land after a bankruptcy declaration and extended the area to create a large suburb. The Geographical Names Board of New South Wales eventually made the decision in late 1981 to divide the area into two separate suburbs named St Clair and Erskine Park, rather than call the whole area