Dinefwr Castle

Castell Dinefwr stands on a ridge on the northern bank of the River Towy near Llandeilo, a hundred feet above the water. Tradition holds that the first castle here was raised by Rhodri the Great, though no archaeological remains have been dated to that period. It became the chief seat of the Dinefwr dynasty of the kingdom of Deheubarth, and of Rhodri's grandson Hywel Dda, first ruler of Deheubarth and later king of most of Wales.

Rhys ap Gruffydd, ruler of Deheubarth from 1155 to 1197, is thought to have rebuilt the castle. He also raised Carreg Cennen some four miles to the south; it cannot be seen from Dinefwr, though Dryslwyn Castle can just be made out on its hill blocking the Towy valley to the south-west. Rhys founded two religious houses in the same period: Talley, the first Premonstratensian abbey in Wales, and Llanllyr, a Cistercian nunnery, only the second nunnery founded in Wales and the first to prosper.

Giraldus Cambrensis tells of a plan by Henry II of England to assault Dinefwr during a campaign against Rhys. One of the king's most trusted followers was sent ahead to reconnoitre, guided by a local Welsh cleric who had been asked to lead him to the castle by the easiest route and instead took the most difficult he could find, ending the performance by stopping to eat grass and explaining that this was the diet of the local people in times of hardship. The attack was duly abandoned.

On Rhys ap Gruffydd's death the castle passed to his son Rhys Gryg, and the earliest parts of the present castle are thought to derive from this period. Llywelyn the Great of Gwynedd was by then extending his influence into the region, and Rhys, finding himself unable to resist, dismantled the castle himself. Llywelyn had it restored, and held it until his death in 1240.

In 1255 Llywelyn the Last gave Dinefwr to Rhys Fychan, later to Maredudd ap Rhys, and later still returned it to Rhys Fychan. Maredudd allied himself with Edward I of England, and his son Rhys ap Maredudd helped Edward capture Dinefwr in 1277. Rhys had apparently been promised the castle in return for that help. Edward did not keep the promise, and in 1291 had him executed.

The castle was now in English hands, and is recorded to have been burnt during the rebellion of Llywelyn Bren in 1316. In 1317 it was granted to Hugh Despenser, the king's favourite. In 1403 the forces of Owain Glyndŵr besieged Dinefwr without taking it.

Towards the end of the fifteenth century Dinefwr was held by Sir Rhys ap Thomas, who carried out extensive rebuilding. In 1531 his grandson Rhys ap Gruffydd was executed for treason and the castle was confiscated by the crown, though the family were later able to recover it. When Newton House was built nearby in 1660 the keep was modified as a summer house, and the remains of its large windows can still be seen at the top of the keep.

The ruin is a Grade I listed building, a scheduled monument and a National Monument of Wales. It is partly owned by the Wildlife Trust of South and West Wales, which makes no charge for entry, and managed by Cadw on the trust's behalf, within Dinefwr Park, which belongs to the National Trust. Since 2024 Cadw have used the Welsh name Castell Dinefwr in English as well, part of an effort to standardise the names in both languages.