 The image shows Stonehenge, a prehistoric monument in Wiltshire, England. It consists of a ring of standing stones, each around 13 feet (4 meters) high, 7 feet (2 meters) wide, and weighing around 25 tons. The stones are set in a circle about 300 feet (90 meters) in diameter. The purpose of Stonehenge is unknown, but it is thought to have been a religious or ceremonial site. It was built in several stages, beginning around 3000 BC. The stones were brought to the site from around 20 miles (32 kilometers). Stonehenge is one of the most famous prehistoric monuments in the world.