- Category: Water Feature
- Type: Other Water Feature
- Latitude/Longitude: 52°35'3"N 3°27'18"W
- Eastings/Northings: 301500, 299500
- OS Grid: SO015995
- Mapcode Local: GBR 9L.B9Z1
- Mapcode Global: WH68S.W9TL
Location and coordinates are for the approximate centre of Nant y Llyn Mawr within this administrative area.
Geographic features and populated places may cross administrative borders.