- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 52°53'5"N 4°0'50"W
- Eastings/Northings: 264578, 333850
- OS Grid: SH645338
- Mapcode Local: GBR 5V.Q9DM
- Mapcode Global: WH55V.9RS5
Location and coordinates are for the approximate centre of Llyn Eiddew-mawr within this administrative area.
Geographic features and populated places may cross administrative borders.