Wiltshire is a county in South West England with an area of. It is landlocked and borders the counties of Dorset, Somerset, Hampshire, Gloucestershire, Oxfordshire and Berkshire. The county town was originally Wilton, after which the county is named, but Wiltshire Council is now based in the county town of Trowbridge. Wiltshire is characterised by its high downland and wide valleys. Salisbury Plain is noted for being the location of the Stonehenge and Avebury stone circles and other ancient landmarks, and as a training area for the British Army. The city of Salisbury is notable for its mediaeval cathedral. Important country houses open to the public include Longleat, near Warminster, and the National Trusts Stourhead, near Mere.