Dinefwr Castle was originally a fortress of the Lord Rhys, the powerful native Welsh overlord of Deheubarth, but it was later seized by the English during the First War of Welsh Independence. Attacked during the Owain Glyndŵr rebellion, the castle was garrisoned for the Lancastrian cause during the Wars of the Roses and thereafter was allowed to drift into ruin.



Dinefwr Castle occupies a ridge of high ground overlooking the River Towy, an important waterway that served as a major communications artery in pre-industrial Wales. The ridge was ideally suited as a defensive site and may well have been an Iron Age (or earlier) fortified settlement. If so, evidence has been buried under the later medieval castle and accordingly the first known fortification in the area was a Roman fort established around AD 70. However, access to the river was more important to the Roman military than a strong defensive position and accordingly their fort was positioned on the flat plains below the ridge. Situated between the outposts at Llandovery and Carmarthen, it was an earth and timber fortification configured in the standard Roman 'playing card' layout. It enclosed an area of over nine acres making it one of the largest known Roman forts in Wales and suggesting it was garrisoned by a cavalry unit. However, occupation was short-lived and the fort had seemingly been abandoned circa-AD 80. Shortly after a second fort, significantly smaller and therefore probably an infantry base, was constructed on the site and this remained occupied until around AD 140. That fort was probably decommissioned as part of a broader reduction of military forces in South Wales.


During the Dark Ages, a small religious community became established nearby and it is possible some form of castle was constructed during this period on the ridge occupied by the later medieval castle. However, to date no archaeological evidence has been found to confirm this theory. The earliest reference to any fortification on the castle ridge dates from the mid-twelfth century when the Brut y Tywysogyon reported that a fortification was seized in 1165 by Rhys ap Grufford, Lord Rhys. He was the ruler of Deheubarth, an area extending across South West Wales, and was sufficiently powerful to resist Anglo-Norman incursion into his territories. However, when he died in 1197 bitter infighting ensued between his sons and later grandsons over who should inherit. Dinefwr Castle was taken on multiple occasions by opposing claimants with the dispute continuing until 1216 when Llywelyn ab Iorwerth (the Great) forced a settlement on the family. Dinefwr Castle was granted to Rhys Gryg, one of the sons of Lord Rhys.


Rhys Gryg married into the powerful Anglo-Norman de Clare family in 1219 and seems to have made significant upgrades to Dinefwr Castle presumably to ensure it was a fitting residence for an individual with his status. His main addition was the circular Keep. Rhys initially opposed Llywelyn ab Iorwerth's decision to pay homage to Henry III and this prompted the Welsh Prince to besiege Dinefwr. However, when faced with the Royal army Rhys surrendered. A letter dated 1220 from Llywelyn to King Henry suggests that Dinefwr Castle was being dismantled, possibly as part of the settlement between the Welsh Prince and Rhys Gryg. This dismantling was probably limited to a portion of the curtain wall only. Upon his death his lands were divided between his heirs with Dinefwr Castle passing first to his elder son Rhys Mechyll and then to his grandson Rhys Fychan.


The 1250s saw increasing friction between Rhys Fychan and his brother Maredudd ap Rhys, who had inherited Dryslwyn Castle from his father, over the extent of their respective territories. The disagreement was made worse by the intervention of LLywelyn ap Grufford who sided with Maredudd ap Rhys effectively disinheriting Rhys Fychan forcing him to approach the Anglo-Normans for assistance. An English army marched in his support but was defeated at Cymerau. However Rhys Fychan was reconciled with LLywelyn and restored to Dinefwr.


The Anglo-Welsh relationship changed significantly upon the death of Henry III in 1272. The English King's successor, Edward I, lost patience with LLywelyn ap Grufford and commenced the First War of Welsh Independence in 1276. By Summer the following year Welsh opposition in the South and East had crumbled. Rhys Wyndod, son of Rhys Fychan, surrendered Dinefwr Castle and submitted to Edward. This saved him but Dinefwr Castle was confiscated and given to the custody of Bogo de Knovil. Coupled with his treatment in the years following this, Rhys joined the forces of Dafydd ap Grufford during the Second War of Welsh Independence which started in 1282. Rhys was captured alive and was sent to the Tower of London for perpetual imprisonment.


For the rest of the thirteenth century Dinefwr remained a Royal castle with repairs made and a number of upgrades built including an enhanced gatehouse and a rectangular hall. It was attacked during a Welsh uprising in 1316 but escaped significant damage and the following year Edward II granted the castle to his unpopular favourite, Hugh Despenser the Younger. This prompted a further attack in 1321 from the Marcher Lords who resented the extending influence of the Despensers and joined a wider revolt led by Thomas, Earl of Lancaster. That rebellion was defeated and the castle returned to the Despensers. However, it was returned to Royal ownership in 1326 following the overthrow of Edward II and the downfall of the Despenser family.


Dinefwr Castle was attacked during the rebellion of Owain Glyndŵr. On 2 July 1403 the castle was besieged by Welsh rebels but, despite furious attempts to seize the castle, the garrison held out and the besieging force ultimately withdrew. The castle remained in English hands and, as the rebellion petered out, it was repaired. Thereafter the castle was placed under the administration of Grufford ap Nicholas whose descendants continued to hold the castle, with the exception of a short period during the Wars of the Roses, for the rest of its operational life. The construction of Newton House in the fifteenth century saw Dinefwr Castle abandoned as a residence and thereafter it was allowed to drift into ruin. A Summerhouse was built atop the circular Keep in the seventeenth century.





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What's There?

Dinefwr Castle consists of the ruins of a medieval, Welsh built castle. The remains include a particularly impressive Round Keep albeit one that has been extensively modified. The castle is located within a National Trust owned park and forms part of a combined visitor attraction with Newton House.

Dinefwr Castle Layout. The castle occupied a ridge of high ground overlooking the River Towy. The castle consisted of two wards with the circular Keep in between them. The Roman Forts were located to the north-east on the flatter ground.

Circular Keep and Summer House. The circular Keep dates from the thirteenth century and was contemporary to similar structures at Bronllys, Skenfrith and Tretower. The ‘windowed’ top is much later - the remains of a Summerhouse built in the seventeenth century.

Dinefwr Castle. Although a CADW property, the castle is set within a National Trust owned park.

South-West Tower.

Curtain Wall.

North-West Tower.

View. The castle overlooked the floodplains of the River Towy. The rise on which Dryslwyn Castle sits can be seen in the centre-right.

Getting There

Dinefwr Castle is a major tourist attraction and accordingly well signposted. It is located within Dinefwr Park which is accessed from Carmarthen Road. There is a dedicated National Trust car park which serves the site. The castle is a 500 metre walk from the car park.

Car Park (National Trust)

SR19 6RT

51.882624N 4.012789W

Dinefwr Castle

No Postcode

51.876736N 4.018165W