Wiltshire is a predominantly agricultural county in the south of England. The county covers an area of almost 1,400 square miles and has a population of just over half a million. The name Wiltshire is from the Saxon settlers known as the Wilsaetan who lived along the Wylye valley (Saetan means settlers). Wiltshire's natural attractions include the Marlborough Downs, Savernake Forest and the rivers Avon, Bourne and Wylye. The county's main products are wheat, cattle, carpets, rubber and engineering. Wiltshire has a rich history. Within the Wiltshire Downs are the ancient Stone Circles of Stonehenge and Avebury (2 of the most famous prehistoric sites in the world), Silbury Hill and a number of White Horses carved into the hillsides. In the north, Wiltshire also has the quaint charm of the villages of Lacock and Castle Combe. Stonehenge itself stands on the Salisbury Plain, a vast expanse of chalk uplands, about 20 miles east to west and 12 miles from north to south, which has long been a training ground for the British Army.