- Category: Water Feature
- Type: Island
- Latitude/Longitude: 52°56'58"N 4°33'31"W
- Eastings/Northings: 228182, 342214
- OS Grid: SH281422
- Mapcode Local: GBR 54.L915
- Mapcode Global: WH447.Y480
Location and coordinates are for the approximate centre of Carreg y Chwislen within this administrative area.
Geographic features and populated places may cross administrative borders.