 Superficially this description of an earthwork with exterior ditch would seem appropriate, however the presence of an enigmatic inner ditch has led many archaeologists to doubt this interpretation.This ditch is separated from the outer rampart by a berm of up to 30 metres in width and, to many, it seems likely that the site actually began as a late neolithic Henge.A small geophysical survey was carried out by Anthony Clark and John Gator in 1981 to determine whether or not an earth bank was ever associated with the inner ditch.