Gaer Penrhôs

Gaer Penrhôs, in Ceredigion, Wales, was a ringwork castle at the summit of a steep hill near the village of Llanrhystud; now all that remains are the outlines of its ringworks. Through the years it has variously been referred to as Llanrhystud Castle and Castell Cadwaladr and has likely been the site of more than one structure.

• http://en.wikipedia.org/wiki/Gaer Penrhôs