Abbey Cwm Hir is located in Powys, north of Cilmeri near Llandrindod Wells. Known in Welsh as Abaty Cwm Hir, it was a Cistercian Abbey founded in 1176 by a Welsh lord, Cadwallon ap Madog. 

Unfortunately, Cadwallon, who was the lord of Maelienydd, was killed three years later by Roger Mortimer of Wigmore, leading to a blood feud between two families. In the process, the abbey, which was remote to begin with, was neglected. The abbey’s prospects improved in the 13th century under the patronage of the princes of Wales, Llywelyn Fawr and Llywelyn ap Gruffydd. Twice the Normans burned abbey granges, which were rebuilt with money from the prince. In 1231, the abbey was fined 200 pounds by the Normans for aiding Llywelyn Fawr. After the death of Llywelyn ap Gruffydd in 1282 at Cilmeri, his headless body was transported in secret to the abbey, where he was buried under the altar.

What remains is a ruin. The abbey’s support of the princes of Wales didn’t endear it to the Norman conquerors, and by the dissolution of the monasteries in the 16th century, only three monks remained. Subsequent centuries were not kind. All that remains are fragmentary stretches of the nave. In the Welsh Guard Mysteries, it is to Abbey Cwm Hir that Rhys, Llywelyn’s loyal retainer, brings his body.