Wrong site mate, this is besides a public path and right of way.
To get "as the crow flies" from the circle to the cave in 100 metres you have to hop a fence that encloses, well nothing actually, just a piece of heath, no sssi or anything.
You could go the long way round but that would mean the toil of a 400 metre walk, the fence wouldn't have been there in the neolithic / bronze age and there are still signs of the old path so i happily take it if i feel the need.
You won't find anything on the net about this one, believe me i've tried.
Huh. ; )