Castles in CarmarthenshireCastles in CarmarthenshireLlandovery Castle - Castell LlanymddyfriLlandovery Castle - Castell Llanymddyfri is a late thirteenth-century, Grade II listed castle ruin in the town of Llandovery in Carmarthenshire, Wales. Carreg Cennen CastleThe imposing ruins of Carreg Cennen Castle sit on top of a dramatic limestone crag, a natural fortress.Carmarthen CastleThe ruins of a 12th Century castle partially reconstructed in the 19th Century.