Nice bit of folklore there Rhiannon, its a place Ive always meant to take a spin up to. Looks like a very impressive cairn and I would say that it is probably a passage tomb also.
It does look very impressive doesn't it, quite a lot of work. It's no wonder it's survived so long and left an impression on the local folklore! It's interesting you say it's probably a passage tomb as well - an added dimension of hidden mysteriousness.
All these interesting places to visit.. perhaps I might as well jack my job in and get out on the road.