Editing Carnedd Llewelyn (section)

==Topography and ascent routes==

Carnedd Llewelyn lies in the middle of the main north-east to south-west ridge of the Carneddau, between [[Carnedd Dafydd]] to the south-west and [[Foel Grach]] to the north. A short subsidiary ridge links it to [[Yr Elen]] to the north-west. It can be climbed from Gerlan, above [[Bethesda, Wales|Bethesda]], taking the path following [[Afon Llafar]] then continuing to the summit of Yr Elen before following the short ridge to Carnedd Llewelyn. Another path starts from Helyg on the [[A5 road (Great Britain)|A5]], taking the track to the reservoir then following the slopes above Craig yr Ysfa to the summit. An alternative is to reach it by following the main ridge, either from [[Pen yr Ole Wen]] or from [[Foel-fras]].

The summit is a flat, boulder-strewn plateau, similar to several of the other mountains that lie in the southern Carneddau. The cliffs below the ridges are well-known rock climbs, notably [[Ysgolion Duon]] (meaning "black ladders") and Craig yr Ysfa.  The flat plateau means that during winter and spring, significant accumulations of snow and blizzards occur on frequent occasions.  The mountain has also been noted for its long-lying snow patches in recent years, with old snow patches known to survive on its southern gullies well into July.  The highest lake in Wales, [[Llyn Llyffant]] lies to the lee of the summit of Carnedd Llywelyn.<ref>{{Cite web|title=Geograph:: Llyn Ffynnon Llyffant - the highest lake... © Eric Jones cc-by-sa/2.0|url=https://www.geograph.org.uk/photo/910130|access-date=2021-07-29|website=www.geograph.org.uk|language=en}}</ref>