This circle is said to consist of seven stones and be the kerb of a wrecked stone cairn. I couldn’t verify this as it stands on forestry commision land and the entrance is blocked by a large set of locked gates with signs warning of prosecution and general unpleasantries to any trespassers.
It wasn’t until I got home and rechecked the map that I noticed a public right of way passing through the plantation, just a little furthur along the road.
Damn....