High Quality Content by WIKIPEDIA articles! The Vale of Ewyas (Welsh: Dyffryn Ewias) is the steeply-sided and secluded valley of the Afon Honddu, in the Black Mountains of south Wales and within the Brecon Beacons National Park. As well as its outstanding beauty, it is known for the ruins of Llanthony Priory, and for several noteworthy churches such as those at Capel-y-ffin and Cwmyoy. It is sometimes referred to as the "Llanthony Valley" as Llanthony is the village situated at the valley centre.