Llanwrin to Dolgellau Gas Pipeline Replacement

Abstract

A watching brief was undertaken along the 23.5 km route of a gas pipeline through mountainous terrain in mid-Wales, passing through Powys, Gwynnedd and Snowdonia National Park. The landscape is very varied, including the Afon Dulas and Afon Llefenni river valleys, the Mynydd Gwerngraig and Cadair Idris uplands, the Afon Wnion river valley as well as hill areas around Dolgellau. Very little significant archaeology was encountered. A single possible prehistoric or Roman cremation burial was identified, but its date and identification as a human burial remain uncertain. Other features identified were few in number and either undated or demonstrably of modern date. The latter included a mill race, structures within a flint quarry and buried footings associated with a sheepfold. The possible lines of Roman Roads between Brithdir (Dolgellau), Cefn Caer Roman fort at Pennal (Machynlleth) and Ffestiniog were investigated at seven locations. At six locations former or current tracks were observed as eroded hollow-ways, but revealed no evidence that could shed light on the early origins of these routeways. A survey of historic boundaries was undertaken to record the profiles of potentially significant boundaries and attempt to recover dating evidence for the origins of the field boundary systems crossed by the pipeline route. No significant dating evidence was recovered. A series of hand auger samples was recovered to assess the palaeoenvironmental potential of relatively shallow surface peat deposits encountered at several locations along the route. None of the sequences were suitable for further analysis – Modern radiocarbon results were obtained from one of the sequences, which could reflect the recent origin of the peat, or contamination, possibly caused by bioturbation. None of the peat sequences were associated with archaeological remains.