by Sandy Gerrard

A short distance south of the car park for Usk Reservoir in the Brecon Beacons at SN83322835 within an area of improved pasture stands a large stone known by the name Gwern Wyddog. This stone is a scheduled ancient monument and the Royal Commission on the Ancient and Historical Monuments of Wales (RCAHMW) describe it as “a lozenge-shaped standing stone, 2.3m high by 1.2m by 1.4m” whilst the Clwyd Powys Archaeological Trust (CPAT) description records it as: “A massive lozenge-shaped stone is aligned NE-SW and measures 1.3m long x 1.3m wide x 2.2m high. The stone is sited on a slight south-east facing slope in a pasture field. Small stones surround the base, and there is one large block on its NW side. All these stones lie within an area of slight sheep scour.”

Photographs of the stone available on the internet confirm these descriptions, but raise possible doubts regarding the explanation that the stone was erected in prehistoric times. There is no published information to confirm its prehistoric credentials and furthermore no other remains of a similar date are currently recorded in the vicinity. It may indeed by a standing stone erected during the Bronze Age – but what is lacking is any evidence to support this position. An alternative explanation that it represents a glacial erratic together with a few later clearance stones would on the face of it have as much credence. Can Cadw be certain that this stone is not entirely natural in origin? Alternatively if the stone has indeed been placed in its present position could it be a rubbing stone, boundary stone or a waymarker? The lack of evidence to confirm the structure as being of prehistoric date does not appear to have been an obstacle to its scheduling. Should it have been? or does it make sense to schedule sites where there is an element of uncertainty?


Large it certainly is but no evidence currently exists to prove that this rock was erected during prehistoric times. Despite a total lack of evidence regarding its date or function it is scheduled as an ancient monument. How could this be? After all Cadw claim they don’t schedule prehistoric sites where there is “insufficient evidence to confirm the structure as being of prehistoric date”. So do Cadw schedule prehistoric sites where there is insufficient evidence or not? It would appear they do – despite their protestations that they don’t.

It is indeed a funny old world with perhaps just a soupçon of inconsistency and a pinch of double standards thrown in for good measure. A fair selection process would ensure that all sites were treated identically and the criteria applied consistently. Sadly such fundamental principles seem to be entirely absent from the Cadw scheduling process. Sometimes inconvenient but pertinent evidence is ignored whilst on other occasions the lack of any evidence is not seen as an obstacle in this surreal decision making process. Consequently, just how robust is the Welsh Schedule of Ancient Monuments?