- Category: Water Feature
- Type: Island
- Latitude/Longitude: 53°25'9"N 4°29'10"W
- Eastings/Northings: 234885, 394270
- OS Grid: SH348942
- Mapcode Local: GBR HM9N.MTP
- Mapcode Global: WH41Z.2B01
Location and coordinates are for the approximate centre of Trwyn y Galen-ddu within this administrative area.
Geographic features and populated places may cross administrative borders.