Terrey Hills is a suburb of Northern Sydney, in the state of New South Wales, Australia 25 kilometres north of the Sydney central business district in the local government area of Northern Beaches Council. It is part of the Forest District and Northern Beaches region. Terrey Hills is a very leafy suburb and in some areas semi-rural, with many people boarding their horses in the area. Terrey Hills owes its name to the two original land holders Samuel Hills and Obediah James Terrey. Obediah Terrey acquired in 1881 and Samuel Hills owned nearby. The area was used by Indigenous people prior to European settlement, and rock carvings exist in some places. One set of carvings is located near Larool Road and depicts hunting scenes with kangaroos, human figures and footprints. Terrey Hills Post Office opened on 17 June 1935. History For the older (geological) history, Terrey Hills is noted as the "laterite capital" of the Sydney Basin for those interested in how laterite forms (which has commonly been taken as indicator of climate change, and signalling former hotter and wetter conditions). The laterite of Terrey Hills was used for early road-making and also has been used for rock wall coastal defence at Collaroy Beach. It is the only place in New South Wales where fossils (meagre plant fibres) have been noted in laterite. The main laterite quarry (now the Terrey Hills playing field), and a smaller one at Tumbledown Dick, are on the National Estate (a Commonwealth heritage listing) and also have been nominated to the NSW Government local-significance heritage listing which in this area is administered by the Northern Beaches Council. A small struggle has been ongoing for years to better protect the laterite exposure at Tumbledown Dick from the announced effects of Mona Vale road widening plans. The laterite was worked during the Great Depression when Australia had one third of the workforce out of work. The Warringah Shire Quarry or 'gravel pit' at Terrey Hills was an important place for the distribution of government relief work funding. Gai Halstead in 1988 wrote a bicentennial compilation which was sponsored by Dick Smith's "Australian Geographical" organisation which was then headquartered at Terrey Hills - "The story of Terry Hills and Duffys Forest". In this it is noted that married men were given work at the rate of two weeks on and one off, whereas the single men worked at