The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Primary Reference Number (PRN) : 02953w
Trust : Glamorgan Gwent
Community : Cilybebyll
Unitary authority : Neath Port Talbot
NGR : SN7314903315
Site Type (preferred type first) : NOT APPLICABLE natural feature / Neolithic Chambered tomb
Status : Scheduled Monument

Summary :
The interpretation of this feature as a monument is not entirely certain; it could be a natural landform, but the question is unlikely to be resolved in the absence of excavation. It consists of a pile of very large slabs of sandstone embedded in a steep hillslope, one of which looks as though it might be a capstone, although most of the rest look like a natural geological formation.

Description :
The interpretation of this feature as a monument is not entirely certain; it could be a natural landform, but the question is unlikely to be resolved in the absence of excavation. An 'old quarry' is marked on the 3rd edn 25" OS map, slightly to the NW of the site, and the characteristics of the site could possibly be connected with other, unrecorded quarrying.
The site consists of a pile of very large slabs of sandstone embedded in a steep hillslope which is clearly prone to instability and the whole pile has obviously undergone slippage. The individual slabs themselves show discontinuities in the bedding planes, which add to the difficulties of interpretation. To the N, the N sides of slabs visible at the top of the hillside form a straight line, but again it is not clear whether this is the result of deliberate construction or is a natural fault line. There is no evidence for a mound.
On the S (downward) side, the presumed capstone (3.45m E-W x 2.25m x 0.55m thick) is propped up on a relatively small slab, which in turn rests on a larger slab, which is however smaller than the presumed capstone. The corner of the capstone is 1.25m above ground level. This arrangement of slabs provides the most convincing support for the idea of its being a tomb, since it looks built rather than natural. None of the rest of the rest of the slabs have this quality. To the north of the two piled slabs is the presumed W chamber, bridged by the capstone, the N side of which rests on a slab projecting out of the hillside. The line of this is roughly continued to the W by two slabs, each projecting further S than the one to its E; any further continuation of the line is towards the W beyond the second slab is disrupted by a mature tree, and the other slabs lying to the W and S may or may not be part of the structure. A possible second chamber was noted in the scheduling report in 1997 as marked by five upright stones, but this did not appear particularly convincing; this presumed chamber was noted as measuring c 2m by 2.5m; the other is possibly 3m by 2.2m.
The situation, on a hillside near the bottom of a dip, is similar to that at Coedparcgarw near Bridgend (PRN 374m).
This site is not the 'cistvaen' noted by Morgan (1923, 23), which was obviously not set into the hillside, and has been given the PRN 5117w. PRN 2953w appears to be the site which Morgan noted with the following words: 'A short distance further up the hillside [from the lost kerb circle or structured cairn PRN 511w], and on the escarpment of the outcrop is a rectangular block about 8 feet long by 4 feet square laid horizontally, one end rests on the scarpment of the rock, the other on a small column very similar to the first, about 4 feet high, and of the same dimensions as the other stone. The top is fairly flat, and I could detect no traces of cup marks.' The main difference between this account and the site as it exists at present is the discrepancy in measurements, but it is clear from the wording that Morgan's are an estimate only.
Reference: Morgan, W Ll, 1923, Carn at Penyralltwen, Rep Royal Institution S Wales 1922-23, 22-3 11.10m E-W x 4.4; height estimated at 1.8m
GGAT 72 Prehistoric Funerary and Ritual Sites survey 2001.

(1923) On slope of N end of hill and immediately below house [sc Pen-yr-Alltwen] were the remains of a large cistvaen about 5ft x 4ft and 3ft deep, partly infilled. Capstone removed c 1919. Adjacent to the cist was a large stone under which was a passage (Source 03) .
(1981) No traces visible - Morgan's description is slightly misleading as whole area is on S end of hill, but thorough search made of area around Pen-yr-Alltwen (now derelict) and below scarp to SW (Source 02).
- as recorded by Llewellyn Morgan. Extant in 1997 at scheduling visit appears to have collapsed down slope since 1920s.
(1997)The site today consists of a number of prominent upright stones, and a particularly large horizontal slab, likely to have been the capstone, which measures 3.1m by 2.3m. The capstone is no longer in its original position, and has broken at its NE corner, probably while being moved.The capstone now rests on top of a number of large upright stones, marking a burial chamber. The tomb is comprised of two burial chambers, one still partially covered by the capstone, the other lying to the E of it and marked by five large upright stones. The E chamber measures approx 2m by 2.5m and the w possibly 3m by 2.2m (although it is difficult to take measurements because of the capstone). A number of other stones could mark further chambers or be the result of stones having been removed around. There are no surviving indications of a covering mound. (Source 04)


Sources :
03/PM Desc Text/Morgan/1922-3/Report of RISW p23
01/PM Desc Text/Doyle J/9.11.95/Proposed New Site Notification Form
02/PM Site Visit Record/Parkhouse J/28.1.81
04/MM Desc Text/Roberts/K/03-12-97/SAM visit description text
01/MM Desc Text/Doyle J/9.11.95/Proposed New Site Notification Form
02/MM Site Visit Record/Parkhouse J/28.1.81

Events :

Related PRNs : 511W, 1021w, 5117w

Compiled date : 26-02-1996

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