- Category: Water Feature
- Type: Island
- Latitude/Longitude: 52°2'44"N 4°31'38"W
- Eastings/Northings: 226778, 241590
- OS Grid: SN267415
- Mapcode Local: GBR D5.F7PC
- Mapcode Global: VH2MY.GVX6
Location and coordinates are for the approximate centre of Ynys Fawr within this administrative area.
Geographic features and populated places may cross administrative borders.