Henge (n):
1) A prehistoric circular earthwork characterised by a non-defensive arrangement of a ditch inside the bank
2) Neolithic or Bronze Age circular enclosure surrounded by one or more banks and ditches, with the ditch usually being inside the bank, sometimes with a stone circle, setting of posts or wooden roundhouses inside. Not all stone circles are henges, as not all have a surrounding bank and ditch.
3) a circular area enclosed by stones or wood posts set up by Neoloithic peoples. It is usually bounded by a ditch and raised embankment.
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