- Category: Water Feature
- Type: Wetland
- Latitude/Longitude: 51°59'44"N 4°58'16"W
- Eastings/Northings: 196110, 237213
- OS Grid: SM961372
- Mapcode Local: GBR CK.JKJP
- Mapcode Global: VH1QM.S36C
Location and coordinates are for the approximate centre of Carreg Ddu within this administrative area.
Geographic features and populated places may cross administrative borders.