Stonehenge is a prehistoric monument located in Wiltshire, England. The site consists of a circular setting of large stones, known as megaliths, surrounded by earthworks that form an enclosure. The largest stones, known as the sarsens, weigh around 50 tons and are up to 30 feet tall. The smaller stones, known as the bluestones, weigh around 4 tons and are up to 6 feet tall. The stones are arranged in a specific pattern, with the largest stones forming a circle and the smaller stones forming a horseshoe shape. The site also features earthworks, including a circular bank and ditch, and several burial mounds. The purpose and meaning of Stonehenge are still unknown, but it is believed to have been built in several stages between 3000 and 1500 BCE.