- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 54°17'42"N 3°5'21"W
- Eastings/Northings: 329206, 489384
- OS Grid: SD292893
- Mapcode Local: GBR 6LVS.Z1
- Mapcode Global: WH71S.J95K
Location and coordinates are for the approximate centre of Allan Tarn within this administrative area.
Geographic features and populated places may cross administrative borders.