St Brynach's Well may possibly have medieval origins. Early medieval cross-carved pillar stone (NPRN 304323) stands some 300m to the south-southwest, and two further early medieval pillar stones (NPRN 304322) are located some 800m to the south-west: St Brynach's well could have been associated with these. The cult of Brynach is the main cult in this part of pembrokeshire, centred on St Brynach's Church, Nevern, and the well is thought to have been a pilgrimage well on the main route to the church. The route reached its peak during the late medieval period, but may have had earlier origins. It may be the St Brynach's Well mentioned by Giraldus Cambrensis, although he may have been referring to St Brynach's Well, Henry's Moat (NPRN 304442). It is referred to by Fenton as `Above that range of rocks called Carnedd Meibion Owen, on the side of the mountain by the highway, and is compassed round with a curtilage of stone wall called Buarth Brynach ? Brynach's fold, the wall being of 6 feet thick?. In 1914 no traces of the stone wall existed. It was later noted that the spring had been diverted, with only a wet hollow indicating the site. When visited by Dyfed Archaeological Trust in 2002 it was not visible.

Sources include:
Cambria Archaeology, 2003, Early Medieval Ecclesiastical Sites Project, Pembrokeshire gazetteer

N Vousden, 16 October 2018