- Category: Geographic Feature
- Type: Valley
- Latitude/Longitude: 52°40'46"N 3°46'19"W
- Eastings/Northings: 280304, 310568
- OS Grid: SH803105
- Mapcode Local: GBR 95.49XW
- Mapcode Global: WH682.1X34
Location and coordinates are for the approximate centre of Cwm Gerwyn within this administrative area.
Geographic features and populated places may cross administrative borders.