- Category: Water Feature
- Type: Inland Water
- Latitude/Longitude: 53°16'14"N 4°20'16"W
- Eastings/Northings: 244197, 377396
- OS Grid: SH441773
- Mapcode Local: GBR HNN1.XCW
- Mapcode Global: WH42T.B2M0
Location and coordinates are for the approximate centre of Cefni Reservoir within this administrative area.
Geographic features and populated places may cross administrative borders.