Degannwy Castle

Has been described as a Certain Timber Castle (Motte), and also as a Certain Masonry Castle

There are masonry footings remains

NameDegannwy Castle
Alternative NamesCastle of Gannoc; Gannock; Dagaunoth; Deganwy; Hegannow
Historic CountryCaernarfonshire
Modern AuthorityConwy
1974 AuthorityGwynedd

Fragmentary shattered ruins of a great stone-built fortress crown the twin peaks of Deganwy Castle. This was Arx Decantorum, the seat of Maelgwn tyrant of Gwynedd in the sixth century, burnt by lightning in 812 and destroyed by the Saxons in 822 AD (see NPRN 404377). In the late eleventh century this was the seat of Robert of Rhuddlan from which he levied extortion on Gwynedd and from which he rode out to his death. As the Castrum de Gannoc it changed hands, was rebuilt and destroyed throughout the thirteenth century. The visible ruins are those of the great castle, accompanied by a borough, built by Henry III in 1245-50 that was beleaguered for seven years before being systematically destroyed by Llywelyn ab Gruffudd in 1263. Some activity continued at the site and the borough was still active in 1305. The castle was excavated in 1961-6, when evidence was recovered for a later prehistoric style fortress on the western peak, along with first to third century Roman material. The main castle court occupied the western crag and enclosed an area about 60m across. It included at least one great round tower and several domestic blocks. The smaller eastern crag was crowned by the irregular Mansel's Tower. The area between the crags was enclosed by great ramparts and walls, with a monumental twin-towered gatehouse on the south-side. Extensive settlement earthworks to the north and south of the castle (NPRN 400533, 400535) may represent several periods of occupation, including the thirteenth century borough (see NPRN 400533). The name attached to this area, 'the Vardre', suggests that it was at some time a bond settlement associated with a local court

(Coflein–John Wiles 27.07.07)

Set across 2 steep hills known as The Fardre inland from the village, with panoramic view across Conwy, estuary, coastline and N Wales mountains.

Although it was a defended site from the early medieval period, extant masonry remains of Deganwy Castle belong to building campaigns of the C13, during which time it was held alternately by both Welsh and English forces. The earliest part of the present structure is the revetment on the N side, of c1213 built by Llywelyn ap Iorwerth. The remainder of exposed masonry was added in the period 1245-54, when the castle was substantially rebuilt by Henry III, but not completed. It was captured in 1263 by Llywelyn ap Gruffudd. When Edward I seized control over the area in 1283 he chose not to rebuild Deganwy but to build a new castle at Conwy.

A fortification between 2 steep hillocks, with bailey between them. The former S entrance retains a short section of rubble-stone wall close to the former gatehouse, and other footings of the wall are also visible. On the N side is a bank and ditch, and a short section of a rubble-stone wall at R angles, probably part of a gateway, although the N wall was never completed. The W hillock retains traces of mid C13 curtain wall to the S and E, with a more substantial earlier surviving section to the NW corner. Here there is the base of a round turret and, at a lower level, a substantial retaining wall, both of coursed rubble stone. No structures are now visible on the E hillock, where Mansells Tower formerly stood. (Listed Building Report)

Gatehouse Comments

It has been suggested that Edward I used the stones of Deganwy to build his new fortress of Conwy although it perhaps more likely that large structural timber, lead and other such, rather than stone was taken. The paltry ruins which can be seen today are mostly from Henry III's fortification, and include the foundations of the gatehouse towers, traces of curtain wall, and the bailey ditches and banks.

- Philip Davis

This site is a scheduled monument protected by law

This is a Grade 2* listed building protected by law

Historic Wales CADW listed database record number
The National Monument Record (Coflein) number(s)
County Historic Environment Record
OS Map Grid ReferenceSH782794
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Primary Sources

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