- Category: Water Feature
- Type: Island
- Latitude/Longitude: 53°13'7"N 4°30'38"W
- Eastings/Northings: 232464, 372020
- OS Grid: SH324720
- Mapcode Local: GBR 56.18Q2
- Mapcode Global: WH42X.PC67
Location and coordinates are for the approximate centre of Cerrig y Defaid within this administrative area.
Geographic features and populated places may cross administrative borders.