The ceremonial henge monument. The monument includes the henge defined by its earthen bank and internal ditch containing a large stone circle within the henge, two smaller stone circles within the enclosure, and the stone setting known as 'The Cove'. Avebury henge is one of the largest known examples of its class and the stone circle which runs around its interior is the largest stone circle in Britain. The henge enclosure consists of a roughly circular ditch and outer bank enclosing an area of roughly 11.5ha. The ditch measures 23m wide at its top and originally had a flat bottom 10m wide and between 7m and 10m below the ground level, cut into the natural chalk.

There were four causewayed entrances into the interior all roughly aligned with the cardinal compass points. The outer bank, which was built with the material excavated from the ditch, measured between 22m and 30m wide at its base and stands up to 5m high. Within the enclosure stood a stone circle of some 100 stones, built c2500 BC. Inside this massive circle stood a further two stone circles. The northern circle contained 27 stones and had an inner horseshoe of stone known as 'The Cove'. These inner stones stand up to 4.8m high.. The southern circle of 29 stones included a 6.4m high central stone known in recent as 'The Obelisk'. These stones all come from the sarsen 'fields' within 3km of the site, mostly on the Downs to the east.