- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 52°43'18"N 3°58'24"W
- Eastings/Northings: 266813, 315609
- OS Grid: SH668156
- Mapcode Local: GBR 8X.1N9Z
- Mapcode Global: WH56M.YV1B
Location and coordinates are for the approximate centre of Llyn Pen Moelyn within this administrative area.
Geographic features and populated places may cross administrative borders.