Location and coordinates are for the approximate centre of Clydach within this administrative area. Geographic features and populated places may cross administrative borders.
Gazetteer of the British Isles (Edinburgh: Bartholomew, 1887). John Bartholomew
Clydach.-- affluent of river Usk, SE. Brecknockshire; rises on Mynydd Llangunider mountain, and flows 7 m. SE. and NE. to the Usk.