- Category: Water Feature
- Type: Island
- Latitude/Longitude: 52°1'29"N 4°59'45"W
- Eastings/Northings: 194545, 240502
- OS Grid: SM945405
- Mapcode Local: GBR CJ.GRD5
- Mapcode Global: VH1QF.CC4M
Location and coordinates are for the approximate centre of Y Penrhyn within this administrative area.
Geographic features and populated places may cross administrative borders.