- Category: Geographic Feature
- Type: Valley
- Latitude/Longitude: 53°5'34"N 3°57'11"W
- Eastings/Northings: 269297, 356852
- OS Grid: SH692568
- Mapcode Local: GBR 5Y.905C
- Mapcode Global: WH54X.7JQB
Location and coordinates are for the approximate centre of Dyffryn Mymbyr within this administrative area.
Geographic features and populated places may cross administrative borders.