Nightbringer | The Arthurian Online Encyclopedia

Caer Wydyr

“Fortress of Glass”
Caer Wydr

A glass fort that is located in Annwfn, the Welsh Otherworld.

Later tradition says that, like Caer Feddwidd, this fort was visited by King Arthur and his company, but they were unable to make its watchman talk to them.

Caer is a Welsh name for a wall or mound for defence – a city or castle wall, a fortress.

The root to this word might be cau, to shut up, to close, to fence, to enclose with a hedge. Cue means a field enclosed with hedges. When the Britons began to build cities they built a fortified wall to surround them, which were called caer.

The name Chester is a Saxonized form of the Latin castruni, a fort (and one of the few words recognised as directly inherited from the Roman invaders), is a common prefix and suffix in English place-names, such as: Colchester, Manchester, Chesterford, Chesterton. In the Danish and Anglian districts “Chester” is replaced with “caster”, such as: Doncaster and Lancaster, but both forms are allied to casirum, a Latinization of the Celtic caer.

See also
Fort of Glass | The Legend of King Arthur

Preiddeu Annwfn | Attributed to Taliesin, c. 900