| Elidir Fawr | |
|---|---|
 Elidir Fawr from Mynydd Perfedd with Marchlyn Mawr below | |
| Highest point | |
| Elevation | 924 m (3,031 ft) |
| Prominence | 212 m (696 ft) |
| Parent peak | Y Garn |
| Listing | Marilyn, Hewitt, Welsh 3000s, Nuttall, Furth |
| Naming | |
| Pronunciation | Welsh: [ɛˈlɪdɪr ˈvau̯r] |
| Geography | |
 | |
| Location | Gwynedd, Wales |
| Parent range | Snowdonia |
| OS grid | SH612613 |
| Topo map | OS Landranger 115 |
Elidir Fawr is a mountain in Snowdonia, north Wales, the northernmost peak in the Glyderau. Its name means 'Big Elidir', named after a legendary warrior king of the 6th century also known as Eliffer Gosgorddfawr (Elidir of the Great Army).[1]
To the north of the summit is a small lake, Marchlyn Mawr, which is the upper reservoir for Dinorwig power station, a pump-storage power station hidden inside the mountain. Water from this lake flows through huge tunnels into the lower reservoir Llyn Peris. From the north, Elidir Fawr is very prominent, and can appear to be higher than the higher mountains behind it.