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Visitor Notice

As of Monday 14 December all staffed and unstaffed monuments will be closed until further notice.

This is following the announcement of the closure of all outdoor attractions in Wales.

For further information on the Welsh Government’s written statement: Updated Covid-19 control plan for Wales, please visit:

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Northern military outpost in a strategic coastal location

Dating back to the 3rd century, Caer Gybi’s position on low cliffs overlooking the sea suggests it was part of a coastal network of defences, possibly linked to the late Roman watchtower at Caer y Twr on the summit of Holyhead Mountain.

The walls of this rectangular fort are extremely well-preserved, standing up to 13ft/4m high and 5ft/1.5m thick. You can also see remains of four corner towers. Occupying a vantage point above the harbour, the 26ft/7.9m north-east tower is the most prominent, though the top section is a later rebuild possibly dating to the medieval period.



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In Holyhead, overlooking the harbour, off A5

For further information, please contact: Traveline Cymru on 0800 464 0000 or National Rail Enquiries on 03457 48 49 50.