Dating from the same era as the pyramids, the mound (1.25 acres²; 80-85m in diameter and 11m high) consists of a cairn of stones enclosed within a circle of 97 kerbstones, some of which are decorated and surmounted by a facing of round granite boulders. The mound was surrounded at a distance of 15m by a great circle of standing stones, most of which are now broken. Three decorated recesses contain stone basins that held the bones of the dead and funeral offerings. The sun's rays penetrated to the inner chamber at the winter solstice.