- Category: Water Feature
- Type: Island
- Latitude/Longitude: 52°0'55"N 4°55'18"W
- Eastings/Northings: 199595, 239238
- OS Grid: SM995392
- Mapcode Local: GBR CM.HCT7
- Mapcode Global: VH1QG.MLWY
Location and coordinates are for the approximate centre of Cerrig Duon within this administrative area.
Geographic features and populated places may cross administrative borders.