Nova: Secrets of Stonehenge

Every year, a million visitors are drawn to the Salisbury Plain, in southern England, to gaze upon a mysterious circle of stones. Who built Stonehenge? What was its purpose? A new generation of researchers is tackling these questions, finding important clues in the landscape surrounding Stonehenge one of the densest concentrations of prehistoric structures in the world. The story of Stonehenge is being rewritten.