- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 53°2'32"N 4°10'56"W
- Eastings/Northings: 253783, 351694
- OS Grid: SH537516
- Mapcode Local: GBR 5M.DBJ7
- Mapcode Global: WH54Z.QSKF
Location and coordinates are for the approximate centre of Llyn Cwmyffynnon within this administrative area.
Geographic features and populated places may cross administrative borders.