This unusual monument appears to be an example of a Neolithic chambered cairn, which is a rare site type in southwest and midwest Wales. Cerrig Clochesti was first described by Ceredigion antiquarian Trevor Lewis in 1927, when he part excavated the site, although did not appreciate its unique characteristics in terms of Ceredigion's prehistoric monuments. Today it survives as a complex of features, most important of which are two large slabs of stone which were the capstones that originally covered two separate underground cists. Before Lewis recorded the site in 1927, these capstones had already been dragged off their chambers.
This record relates to the eastern cist. This seems to have been associated with the substantial amount of stone spread downslope, to the northeast of the cist.
The stone spread is almost 1 metre thick and presumably the remains of a cairn that completed the monument when it was first constructed. The whole monument measures about 8.5 metres long, northeast to southwest, and is widest at its northeastern end at 6 metres wide, narrowing to 3.5 metres wide at the southwestern end.
The cist is at the upper or southwestern end of the monument. The site was noted by Paul Sambrook during the 1990s and recorded in the regional Sites and Monuments Record at that time. It was noted then that the cists were lined with drystone revetment walls, although by 2012 denser vegetation across the site effectively obscures this detail. The cist is now about 1 metre long by 0.7 metres wide and 0.5 metres deep. Lewis, in 1927, recorded that the cists here were up to `four feet? deep.
The capstone that once covered the cist is a massive slab of stone. It measures a little over 3 metres long, north to south, by 2 metres wide and is at least 0.40 metres thick. Interestingly, the slab is not earthfast, but has slid downslope to rest on the loose stones that formed the body of the associated cairn. There remains a gap between the bottom of the slab and most of the stones beneath it. R.P. Sambrook, Trysor, 28 March 2013
