The Cistercian abbey of Cwm-hir is of great historical significance. Its early history is somewhat obscure but the permanent foundation dates to 1176, probably under the patronage of Cadwallon ap Madog of Maelienydd, as this area of Powys was then known. It was twice attacked during the late twelfth century by Hugh de Mortimer and eventually given a Norman charter. From 1197 onwards, the earlier wooden building began to be replaced by a more permanent stone structure and, although it was never fully completed, the abbey was, at this time, of a size that was only surpassed by those at Durham and Winchester. During the thirteenth century, Llywelyn ab Iorwerth ('Llywelyn Fawr') embarked upon an ambitious building programme which, again, was left uncompleted. He wanted to rebuild the abbey as a great national cathedral which would reflect Welsh political and religious independence under his rule. However, his efforts did not go un-noticed by the English king, Henry III, who imposed a huge fine upon the abbey, seemingly as a result of an alleged act of 'rebellion' by one of its monks. This fine crippled the abbey and effectively stopped its development as a national cathedral. There is a also long-standing tradition, based on the evidence of one chronicle, that the body of Llywelyn ap Gruffudd was buried at Abbey Cwmhir after his death at Cilmeri, near Builth Wells, in 1282. The abbey was further attacked in 1402, during the Owain Glyn Dwr uprising, when it was a stronghold of the Mortimer family, and never fully recovered from the damage sustained at that time. Source: Radnorshire Museum