Avebury is a Neolithic henge monument containing three stone circles, around the village of Avebury in Wiltshire, in southwest England. The word henge refers to a particular type of earthwork of the Neolithic period, typically consisting of a roughly circular or oval-shaped bank with an internal ditch surrounding a central flat area of more than 20 m (66 ft) in diameter.

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.

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.

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