Tolborough Tor Cairn

Tolborough Tor sits high overlooking the A30 and Jamaica Inn. Bit of a climb from the road (see my directions for Tolborough Menhir) but the views north to Brown Willy are superb.
It is a cairn built into the natural rock of the tor and it is difficult to make out what is natural and what is man-made. Simmerly I can not decide if the cairn was at one time much higher or if it just had a covering. A ‘ramp’ enters the central plateau from the south east and then you have the large flat slabs sitting on the surface, were they originally covered? and was the ramp the entrance Sabine Gould talked about in his novel ?(see Rhiannons Folklore posting).