Avebury and Silbury Hill, Wiltshire
The large henge at Avebury with its internal stone circles has a diameter of about 400m and probably dates from about 2600 BC. In the distance is the massive mound of Silbury Hill, which was built around 300 years later. These sites formed part of a major complex of Neolithic ceremonial monuments. They are now in the care of English Heritage (2010).