- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 51°43'18"N 3°35'10"W
- Eastings/Northings: 290525, 203759
- OS Grid: SN905037
- Mapcode Local: GBR HD.2LNK
- Mapcode Global: VH5GC.SZFG
Location and coordinates are for the approximate centre of Llyn Fach within this administrative area.
Geographic features and populated places may cross administrative borders.