- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 52°56'48"N 4°8'23"W
- Eastings/Northings: 256326, 340956
- OS Grid: SH563409
- Mapcode Local: GBR 5P.LGVC
- Mapcode Global: WH55L.C6XB
Location and coordinates are for the approximate centre of Llyn Cwm-bach within this administrative area.
Geographic features and populated places may cross administrative borders.