Trust Regional Historic Environment Record
Priory Church of St. Seiriol, Penmon
Primary Reference Number (PRN) : 6621 Trust : Gwynedd Community : Llangoed Unitary authority : Ynys Mon NGR : SH6303280729 Site Type (preferred type first) : Medieval CHURCH Status : Listed Building I
Summary : The original monastery of Penmon was reputedly founded in the 6th century AD by St Seiriol, the preacher and friend of St Cybi. The site prospered, and in the 10th century crosses were erected at the gates, although Viking raids have destroyed all other evidence from this early period. In the 12th century, during the revival led by Owain Gwynedd and Gruffydd ap Cynan, the abbey church (which is on the northern side of the site) was rebuilt. What is visible today is the most complete example of a church of this period in Gwynedd. By 1414 Penmon had become an Augustian priory and had survived the Edwardian conquest, but was eventually dissolved in 1538 when the site passed to the Bulkeleys of Beaumaris.
The oldest part of the priory church of St Seiriol is the nave, which was built in the mid 12th century. In the later years of the 12th century, the central tower and the north and south transepts were constructed. The chancel is said to have been built during the reign of Llewelyn ap Iorwerth (AD 1220-40) and has since been rebuilt twice: first in the 15th century; and then in 1855, when the earlier walls were rediscovered and the new walls built on the old foundations. The church has number of interesting features including the squat pyramidal stone spire, and the richly carved pillars and arches at the base of the tower which are decorated with chevrons and chequer-patterns of the Romanesque style.