- Category: Water Feature
- Type: Island
- Latitude/Longitude: 51°48'31"N 4°12'47"W
- Eastings/Northings: 247520, 214542
- OS Grid: SN475145
- Mapcode Local: GBR DL.X7KT
- Mapcode Global: VH3LQ.XSJT
Location and coordinates are for the approximate centre of Ynys Isaf within this administrative area.
Geographic features and populated places may cross administrative borders.