- Category: Geographic Feature
- Type: Valley
- Latitude/Longitude: 52°51'19"N 3°33'26"W
- Eastings/Northings: 295234, 329796
- OS Grid: SH952297
- Mapcode Local: GBR 6G.S0CW
- Mapcode Global: WH67D.BH8B
Location and coordinates are for the approximate centre of Cwm Hirnant within this administrative area.
Geographic features and populated places may cross administrative borders.