To most passers by, these are just large piles of stones. However, they are Neolithic chambered cairns, and have been here for at least four thousand years.
The Historic Environment Record provides the following information: "A prominent, probably chambered cairn about 20' high and 90' in diameter, of relatively small, rounded boulders, partly turf-covered. There has been some robbing and disturbance, especially on the SW side near the top, but this appears to be quite superficial. The sides are steep, but the angle becomes more gentle near the edges giving the cairn a slightly bell-shaped profile. At the very edge of the cairn there is a kerb of stones, set either flat or on their long edges. The kerb-stones appear to have been contiguous originally, and remain so on the NE segment. Kerb-stones at short intervals can be traced round most of the east half and occasionally round the rest of the cairn. The stones seem to have varied considerably in size; the largest is 3' 2" high and about 6' long and others are 4' long, but some are relatively small. The profile of the cairn and the fact that the cairn material does not appear to have fallen outside the kerb suggests that the kerb originally edged a platform extending beyond the actual edge of the cairn.
Another cairn showing some constructional similarities and probably chambered lies to the south (NG24SE 12).
RCAHMS 1928; Information from MS of A S Henshall's 'Chambered Tombs of Scotland' Vol. 2, visited 24 October 1962."
Historic Environment Record website - Link