- Category: Water Feature
- Type: Wetland
- Latitude/Longitude: 53°22'12"N 4°15'53"W
- Eastings/Northings: 249414, 388304
- OS Grid: SH494883
- Mapcode Local: GBR HMVS.M4Z
- Mapcode Global: WH428.GKB8
Location and coordinates are for the approximate centre of Graig Ddu within this administrative area.
Geographic features and populated places may cross administrative borders.