English: Avebury is a Neolithic henge monument containing three stone circles, around the village of Avebury in Wiltshire. One of the best known prehistoric sites in Britain, it contains the largest megalithic stone circle in the world. It is both a tourist attraction and a place of religious importance to contemporary pagans. Constructed over several hundred years in the Third Millennium BC, during the Neolithic, or New Stone Age, the monument comprises a large henge (a bank and a ditch) with a large outer stone circle and two separate smaller stone circles situated inside the centre of the monument. Its original purpose is unknown, although archaeologists believe that it was most likely used for some form of ritual or ceremony. The Avebury monument is a part of a larger prehistoric landscape containing several older monuments nearby, including West Kennet Long Barrow, Windmill Hill and Silbury Hill.