- Category: Geographic Feature
- Type: Valley
- Latitude/Longitude: 52°51'48"N 3°23'47"W
- Eastings/Northings: 306088, 330474
- OS Grid: SJ060304
- Mapcode Local: GBR 6N.RPGN
- Mapcode Global: WH78L.S9V3
Location and coordinates are for the approximate centre of Cwm-Rhiwiau within this administrative area.
Geographic features and populated places may cross administrative borders.