- Category: Water Feature
- Type: Other Water Feature
- Latitude/Longitude: 51°57'58"N 3°54'55"W
- Eastings/Northings: 268500, 231500
- OS Grid: SN685315
- Mapcode Local: GBR DZ.L9FP
- Mapcode Global: VH4HL.2TWY
Location and coordinates are for the approximate centre of Afon Marlais within this administrative area.
Geographic features and populated places may cross administrative borders.