The Keeper arrived and was mildly dissapproving. He didn't know the site was there, which is not surprising as these stones are well hidden by the grass. None of them are upright. The nearby area towards the road is littered with industrial archaeology, making me wary of interpretations of the many other large stones in the 200m(ish) radius I explored.
Look for areas where the grass is thin, with more heather and moss hummocks, these seem to be the areas with the "arrays". If you're heading from the B-road, the site is on a slightly sloping flat area, just after the marshy bit. There's a low, linear bank and ditch affair about 60m to the east.
There's no walls to climb over, but the going would be difficult for wheelchair access.