Castell Caer Seion

Castell Caer Seion
Telenarn · CC BY-SA 4.0

Also known as: Caer Seion, Caer Sion, Castell Caer Lleion, Conwy Mountain, Mynydd Y Dref, Sinadon, Синадон

Castell Caer Seion is an Iron Age hillfort situated at the top of Conwy Mountain, in Conwy County [1]. It is unusual for the fact that the main fort contains a smaller, more heavily defended fort, complete with its own distinct defences and entrance, with no obvious means of access between the two [1]. The construction date of the original fort is still unknown, but recent excavations have revealed evidence of occupation as early as the 6th century BC, whilst the smaller fort can be dated with reasonable certainty to around the 4th century BC [1]. Whilst the forts were constructed in different periods, archaeologists have uncovered evidence of concurrent occupation, seemingly up until around the 2nd century BC [1]. The larger fort contained around 50 roundhouses during its lifetime, whereas examinations of the smaller fort have turned up no more than six [1]. The fort is on the summit of a ridge of rhyolite at an altitude of approximately 800 feet and is enclosed by a single rampart [1]. The site has a commanding position overlooking Conwy Bay [1].

Text: Wikipedia – 'Castell Caer Seion' (revision of 2026-07-20), CC BY-SA 4.0 · sentences selected and shortened by an AI system · source →
TypeFortress/citadel
Period1500 - 500 BC
CountryWales
Coordinates53.2827° N, 3.8623° W

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