      salisbury plain is a chalk plateau in central southern england covering ."salisbury plain", encyclopaedia britannica. accessed 11 february 2006. it is part of a system of chalk downlands throughout eastern and southern england formed by the rocks of the chalk group and largely lies within the county of wiltshire, with a little in hampshire. the plain is famous for its rich archaeology, including stonehenge, one of england's best known landmarks. largely as a result of the establishment of the defence training estate salisbury plain (dte sp), the plain is sparsely populated and is the largest remaining area of calcareous grassland in north-west europe. additionally the plain has arable land, and a few small areas of  beech trees and coniferous woodland. its highest point is easton hill. ==physical geography== thumb|on walbury hill, a typical salisbury plain landscape the boundaries of salisbury plain have never been truly defined, and there is some difference of opinion as to its exact area.james, n. d. g. (1987) plain soldiering. hobnob press the river valleys surrounding it, and other downs and plains beyond them loosely define its boundaries. to the north the scarp of the downs overlooks the vale of pewsey, and to the north west the bristol avon. the river wylye runs along the south west, and the bourne runs to the east."english nature salisbury plain sssi citation the hampshire avon runs through the eastern half of the plain and to the south the plain peters out as the river valleys close together before meeting at salisbury. from here the avon continues south to the english channel at christchurch. the hampshire downs and the berkshire downs are chalk downland to the east and north of salisbury plain, and the dorset downs and cranborne chase are to the south west. in the west and north west the geology is mainly of the clays and limestones of the blackmore vale, avon vale and vale of wardour. amesbury is considered the largest settlement on the plain, though there are a number of small villages, such as tilshead, [[ch
Geography_of_Wiltshire Geology_of_England Hills_of_Wiltshire History_of_Salisbury Plains_of_England Plateaus_of_England Proving_grounds Sites_of_Special_Scientific_Interest_in_Wiltshire Special_Areas_of_Conservation_in_England