Wales · Partial ruin
Caer Gybi
Caer Gybi is a late-Roman coastal fortlet located at the centre of Holyhead on Anglesey, built in the 3rd–4th century as a small naval base and watch post. The site preserves substantial lengths of its three defensive curtain walls and the bases of circular corner towers, with later medieval and religious buildings occupying the interior in subsequent centuries.
Its prime
350
Today
Partial ruin
As it stood in 350
The shape it held in its prime.
A compact Roman fort with three roughly rectangular curtain walls built of grey local rubble laid in a coarse herringbone pattern, walls about 4 m high and 1.5 m thick. Each corner featured a circular watch tower; the north-east tower is the most prominent, rising to about 7.9 m. One side of the fort faced the sea and opened onto a stone quay and slipway. At its prime the walls and towers formed a continuous, intact defensive enclosure.
Its story
The story of Caer Gybi.
Caer Gybi was a small fortlet and naval base of Roman Wales, built in the 3rd or 4th century in the province of Britannia Superior. It stands at the centre of Holyhead on Anglesey, with three defensive walls and a circular watch tower at each corner; the fourth side fronted the sea, and was probably the site of a quay for the patrolling Roman warships.
The herringbone-patterned walls stand 4 metres high and 1.5 metres thick. The most prominent surviving corner tower, at the north-east, rises 7.9 metres, though its top section was possibly rebuilt in the medieval period; excavation outside the northern walls uncovered an adjoining, likely Roman, building at the north-west tower. In later centuries medieval and religious buildings came to occupy the interior.
Step inside
6 places to explore in 350.
The record describes 6 distinct spots at Caer Gybi — including 1 interior: interior of the north-west adjoining building. Create your own photoreal reconstruction and walk through every one — more scenes means more photos, more angles and more rooms of the immersive experience.
Create History
Recreate Caer Gybi with AI to explore it.
The artist rebuilds it as it stood in 350 — a photoreal walk that belongs to you alone. Pay with coins, no subscription needed.
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