- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 52°45'46"N 3°54'37"W
- Eastings/Northings: 271189, 320075
- OS Grid: SH711200
- Mapcode Local: GBR 5Z.Z4KK
- Mapcode Global: WH56G.XT18
Location and coordinates are for the approximate centre of Llyn Tan-y-graig within this administrative area.
Geographic features and populated places may cross administrative borders.