Abbeycwmhir

Abbeycwmhir or Abbey Cwmhir (, "Abbey in the Long Valley") is a village and community in the valley of the Nant Clywedog in Powys, Wales. The community includes the hamlet of Bwlch-y-sarnau. It was historically in Radnorshire.

== The Abbey == The village is named after Cwmhir Abbey, the Cistercian abbey built there in 1143. It was the largest abbey in Wales, but was never completed. Its fourteen bay nave was longer than Canterbury and Salisbury Cathedral naves and twice as long as that at St. Davids. It was a daughter house of Whitland Abbey, and was constructed at the behest of three sons of Madog, the then Prince of southern Powys. The first community at Dyvanner (, "Manor House") failed because of the intervention of Hugh de Mortimer, Earl of Hereford, but in 1176 Rhys ap Gruffydd of Deheubarth re-established the Abbey on land given by Cadwallon ap Madog. Llywelyn ap Gruffudd is buried near the altar in the nave.