I've listed this site as a cairn to reflect what it says on the map, but to me it looks more like a bell barrow. The large central mound - which has apparently been extensively robbed and now has a flat top - seems to be made of earth rather than stones, and is covered in grass. Around its base there is a clear ditch and bank.
This struck me as quite a sad site, despite it being in quite an atmospheric woodland setting. Around about the cairn brambles, ferns and nettles are quite overgrown, but the cairn itself is clear - the Woodland Trust (who run Huntly Wood) periodically clear the site of vegetation.