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Deganwy Castle

The twin rocks of Deganwy have been the focus of settlement and warfare for more than 1000 years.

Because they have been fought over so ferociously, there is little remaining for us to see.

Even though the castle walls have been reduced to little more than rubble the hilltop has still left us an intriguing insight into this once grand stronghold.

Roman period

Excavations in 1961-66 uncovered evidence of Dark age and Roman occupation on the larger west hill of the Castle. 5 Constantine coins, were found on the south slope of the west hill and an unidentified Roman coin was found in the mortar of the wall around the east hill. Samian ware (fine imported glazed pottery) was also found during excavation.

Dark Ages

6th Century Degannwy became the Llys ( fortified court) of the fearsome Maelgwyn, Lord of Anglesey,who died in 547 AD
822 AD The Annals Cambriae state that the fortress of Degannwy, described as Arx Decantorum. was destroyed by the invading Saxon army of Ceolwulf of Mercia. The Saxon army did not stay.

Medieval Period

1080 Robert of Rhuddlan built the first Norman Castle on the site while trying to subjugate North Wales,He was killed while bravely attacking some Welsh pirate ships under the nearby Great Orme headland

1200 It was possessed by Llewelyn Fawr


1210 the Castle was made indefensible by Llewelyn during an English advance.1213 the Castle was recaptured from the English by Llewelyn Fawr who built a stone castle here


1241 after Llewelyn`s death his son Dafydd succeeded him and proceeded to slighted (made indefensible) the castle again during the advance of the English army of Henry 3rd A peace treaty was signed and Henry gained the Castle together with Mold and Basingwerk castles and began to rebuild it.

1244 Castle refortified due to Welsh hostilities

1250 Henry ordered the bailey between the two hills to be refortified and Mansell's tower to be raised by 12ft.A chapel was also built just outside the north side of the bailey in Gannoc.

1252 Royal Charter granted to Gannoc and the pipe roll (records)

For 1250-5 records a rent of 10 shillings

A letter from Deganwy during Henry`s 1254 campaign tells vividly of the hardships and lack of food in the castle.

Prisoners were slaughtered on both sides and the heads of Welshmen were brought back to the castle as trophies after each successful sortie.

1257 Castle attacked by Llewelyn ap Gruffudd

1263 Prince Edward, later to be King was able to replenish the castle with food but the Welsh starved the garrison out by cutting off his resupply chain.

Llewelyn ap Gruffydd then slighted the castle so that it was never to be raised again.

1277 The English were once again encamped at Deganwy after a successful invasion under Edward 1.

The King arrived here from Rhuddlan after agreeing the disposal of North Wales with Llewwelyn`s traitorous brother Dafydd.

Edward decided to build a new castle across the river on a prominent rock jutting out into the River Conwy where it could be supplied by sea via a fortified dock.

Local tradition has it that the stone of Deganwy castle was reused in the making of Conwy Castle and it`s Town walls an ignominious end to a once proud fortress that had lasted for a thousand years.