Castell is a small, rectangular, earthwork defended enclosure occupying the flat top of an inland promontory at 40m above sea level, 170m from the coast at Cwm-yr-Eglwys. The enclosure is lies some 150m north-west of St Brynach's Church (NPRN 304400) and the two may be associated, the church site possibly being early medieval in origin. Immediately to the north, east and south of the enclosure the land falls steeply away to sea level. The enclosure does not make use of these steep slopes in its defensive circuit, but relies on a constructed bank and ditch set back from the break of slope. To the west land rises gently away from the site.

The defences are most pronounced on the north side, where they seem to incorporate a natural, low break of slope. Here a c.10m wide bank rises c.0.5m above the interior and 3m over a shallow (0.5m deep) ditch, which is 5m wide. A break in the bank and ditch in the centre of the north side indicates the position of a simple entrance. On the west side the defences run parallel and close to a hedge-bank. The defensive bank is here 1m high externally and internally, with traces of a ditch between the defensive bank and the hedge-bank. The south and east sides are defined by scarp slopes. In 2006, the site was under dense gorse scrub and brambles, which were impossible to penetrate. The interior could not be examined owing to the vegetation, and the west and south defences and exterior on these sides could only be glimpsed.

The Ordnance Survey in 1974 described the enclosure as 60m E-W and 50m N-S, with a level interior. Traces of a 2-cell rectangular building 24m x 8m were noted in the interior. The interior was then largely clear of vegetation.

The Ordnance Survey noted two small quarries close to the enclosure - these were not seen in 2006 owing to the vegetation. Many badger runs were noted over the earthworks in 2006, but there did not appear to be any setts in the enclosure itself. Slight surface weathering over the banks revealed their earth and shalely-stone construction.

Remote sensing was found to be of little use on this site. The site is not visible on aerial photographs owing to the dense tree cover and the LiDAR data was not high enough resolution to define the earthworks.

Reference:

Page, M., Barker, L., Driver, T. and Murphy, K. 2008. Remote sensing and the Iron Age coastal promontory forts of Pembrokeshire, Archaeology in Wales 48, 27-38.

T. Driver, RCAHMW