According to tradition, Penmon Priory was founded in the 6th Century by St. Seiriol. The monastery grew in size, and by the 10th Century, a wooden church stood on the site. This was destroyed by fire when the Vikings sacked it in 971AD. It survived the first Norman invasion of Gwynedd between 1081AD and 1100AD, defended by Prince Gruffydd ap Cynan of Gwynedd. He subsequently built a stone church at the site between 1120AD-1123AD.

Under the patronage of Llywelyn the Great (who ruled most of Wales until 1240AD) and his successors, the priory grew in wealth. During the 13th Century, it operated under Augustinian rule, and was enlarged at this time. In the 16th Century, further domestic buildings were added, including a kitchen and warming house.

Having survived a turbulent few hundred years relatively unscathed, Penmon Priory was eventually dissolved in 1536AD. By this time, it had already fallen into decline, and only the prior and two canons remained in residence.

Following the dissolution, the priory fell into the hands of the Bulkeleys of Beaumaris, who enclosed the land as a deer park. They converted the prior's lodge into a house, and built the dovecote that still stands nearby. Throughout this period and up until the present day, the priory church remained in use as a place of worship.

Two 10th Century crosses once stood in front of the monastery gates. These both survive, and are now displayed within the priory church. Despite being heavily weathered, the decorative engravings are still visible.

Behind the church, a path skirts the old monastic fish pond, leading to a cliff with a holy well springing from its base. The buildings that currently enclose it are relatively recent, but it is likely that the well served as a place of pilgrimage when the monastery was first founded. It is possible to speculate that it may have pre-Christian connections.

Today, the 12th century priory church remains standing in excellent condition. The southern range survives as a ruin, and would once have housed the refectory and dormitory. The western range survives as a private residence, but the eastern range is totally destroyed.

Tucked away in a quiet corner of Anglesey, Penmon Priory enjoys a relatively peaceful setting. This isn't a busy part of Wales, and it's quite easy to enjoy some solitude when visiting this site. This is definitely a hidden gem, and well worth a visit.