Caer Gybi Roman Fort, Historic Sites and Archaeological Sites Holyhead, Anglesey - Wales where to go, what to see and where to stay in Wales

Caer Gybi, the Roman Fort, is a stoutly walled rectangular enclosure that crowned a low cliff overlooking the harbour in Holyhead, Anglesey. It is thought to be a late Roman (third or fourth century AD)Fort and naval base used to defend the Island from marauding pirates in the Irish Sea. After the departure of the Romans from Britain the site was gifted to Cybi by Maelgwyn, the 6th Century King of Gwynedd, where he founded a monastery. To this day the remains of the walls of the Roman Fort butt up to the walls of St Cybi's Church and indeed form a peaceful area within the town of Holyhead. The remains of the Roman walls, with the corner towers still standing, are some 13ft, 4m, in height and 5ft, 1.5m thick with the corner towers being 16ft, 5m in diameter.