- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 51°40'47"N 2°53'21"W
- Eastings/Northings: 338604, 198292
- OS Grid: ST386982
- Mapcode Local: GBR JB.57XD
- Mapcode Global: VH7B1.V1VF
Location and coordinates are for the approximate centre of Rail y Deri within this administrative area.
Geographic features and populated places may cross administrative borders.