Pentre Ifan is a portal dolmen dating to about 3,500 B.C. Its 16-ton capstone, supported by only three uprights and aligned approximately north-south, is over 5 metres long and up to 3 metres in height. The southern (higher) end of the sloping capstone is above the “front” of the monument, where uprights frame a roughly semi-circular entrance area that was once paved with packed cobblestones. The dolmen was erected within in a hollowed-out oval pit and once partially covered with a stone mound extending to the rear (north). The only artefacts excavation revealed in the dolmen were some Neolithic pottery and flint tools.
This monument is located at SN 099370, in an agriculturised valley between the two main exposed upland areas of Preseli. It is outside the main focus area of the current Pilot Study but would come within the larger remit of the full Landscape & Perception project. We visited it because it is a good monumental example showing how important Preseli was considered in Stone Age times, and is of particular interest in visual mapping as it has been noted that the slope of the dolmen’s capstone echoes the angle of the Carn Ingli ridge visible on the western skyline from Pentre Ifan (see fig.1). Carn Ingli (“Hill of Angels”) was considered sacred up until early Christian times, when local anchorite, St. Brynach, would repair to the peak to fast and have visions of angels. The hill also harbours noteworthy magnetic anomalies. Also, the striking, highly distinctive rock clusters known as Carnedd Meibion-Owen are visible precisely on the southwestern skyline from Pentre Ifan. We took the opportunity of our visit to make a preliminary acoustical investigation of Pentre Ifan (see fig.2).