- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 53°2'37"N 3°24'47"W
- Eastings/Northings: 305353, 350537
- OS Grid: SJ053505
- Mapcode Local: GBR 6M.DCCF
- Mapcode Global: WH77M.JRWH
Location and coordinates are for the approximate centre of Llyn Derwen within this administrative area.
Geographic features and populated places may cross administrative borders.