The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

The following information has been provided under the terms and conditions of access as detailed on GGAT’s website  Copyright is reserved on all data supplied by the GGAT HER Charitable Trust. All output resulting from the use of the data must acknowledge the source as follows:-
Derived from information held by the GGAT HER Charitable Trust copyright.

The data below is intended to be used for information and research only and is not for use as part of a commercial project.  If you wish to use information derived from material held by the GGAT HER Charitable Trust for publication in printed or multimedia form or to compile resources for commercial use, prior permission must be obtained in writing. For further information or to arrange a visit to the Trust please send an enquiry form to

Ysgyryd (Skirrid) Fawr hillfort

Primary Reference Number (PRN) : 01497g
Trust : Glamorgan Gwent
Community : Llantilio Pertholey
Unitary authority : Monmouthshire
NGR : SO33111827
Site Type (preferred type first) : Iron Age Hillfort
Status : Scheduled Monument

Summary :
A double enclosed area identified on the bleak ridge of Ysgyryd Fawr, from a private aerial photograph taken in 2000. Earthworks interpreted as a possible Iron Age hillfort or as a religious enclosure.

Description :
A double enclosed area identified on the bleak ridge of Ysgyryd (Skirrid) Fawr hillfort, from a private aerial photograph taken in 2000. Earthworks interpreted as a possible Iron Age hillfort or as a religious enclosure. Site contains the medieval chapel of St Michael (01473g). (01)

Early interpretation of this site has suggested a small enclosure, with the Scheduled remains of the medieval chapel dedicated to St Michael perched on the highest point of this long narrow ridge. Inspection of APs and a site visit has indicated that this site has much more to it.
The first and innermost enclosure noted on OS cards may be IA in origin, but may also be related to the later chapel, the earthworks of the latter taking up much of the internal space of the former and making interpretation of this first inner enclosure less clear. This enclosure is almost kidney-shaped, with the rectangular depression of the chapel remains and a second more circular earthwork sitting within its interior.
A second sub-rectangular enclosure sits concentrically around the first. At its greatest distance on the summit of the ridge it is at a distance of 50-60m south of the first enclosure, however as it curves around the slopes of the north eastern end of Skirrid Fawr this distance lessens to between 30-40m. On the western side the defences sits precariously on the edge of the large quarry which has subsumed much of the north-western side of Skirrid Fawr including some of this western defence.
A third enclosure can be traced enclosing the previous two enclosures. At its greatest distance on the summit ridge this third defence lies at a distance of about 100m south of the second enclosure. As this enclosure curves round the mountain side this distance lessens until the enclosure joins with the southern defences of the second enclosure.
The second and third enclosures can clearly be seen as earthworks, and it is possible a fourth enclosure lies within these, of the same shape, however this has been discerned only from the AP and not from a field visit. A full topographic survey of this entire area would certainly shed more light onto the exact nature of these earthworks. A possible house platform can be seen immediately outside of the first enclosure, and further house platforms and a small quarried area exist just within the bounds of the third enclosure. It is not possible to date these satisfactorily without further investigation.
A much larger, longer length of rampart can clearly be seen from aerial photographs to continue along the entire western edge of the mountain, beginning in the north at the quarry (presumably this continued further north originally), and following the contour of Skirrid Fawr until the mountains most southern point has been reached. This rampart is about 1m wide with the outer bank standing in places up to 0.5m high.
The banks of the second and third enclosures also stand at about 0.5m high and have a width of approximately 1m each. (Wiggins 2006)

Sources :
Wiggins, H , 2006 , Prehistoric defended enclosures in Gwent ( © GGAT)
01/Mm AP Gazeteer/2004 January/Sorrell John/Aerial Archaeological Photographs of Gwent/SMR

Events :
E001515 : Ysgyryd (Skirrid) Fawr hillfort (year : )
E001550 : Prehistoric defended enclosures Gwent (year : 2006)

Related PRNs : 01473g, 400378

Compiled date : 03-02-2004

March 22, 2019, 10:02 am - HTML file produced from GGAT HER Charitable Trust Ltd. Heathfield House, Heathfield, Swansea SA1 Tel. 01792 655208; Fax 01792 474469 website:  email: Registered Charity no. 505609
Data supplied by in partnership with Local Authorities, Cadw and the partners of ENDEX © GGAT HER Charitable Trust, 2019 (and in part © Crown, 2019).