is a
Mountain in the
Carneddau range in
Snowdonia ,
Wales . It is the highest point of the Carneddau and the second highest (see
Relative Height ) peak in Wales.
It is thought to be named after one of the two Welsh princes named Llywelyn in the
Thirteenth Century , but it is not known whether this is
Llywelyn The Great or his grandson
Llywelyn Ap Gruffydd .
It 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. Its position means that any route to this summit involves a long walk. It can be climbed from Gerlan, above
Bethesda , taking the path following
Afon Llafar then continuing to the summit of Yr Elen before following the short ridge to Carnedd Llywelyn. Another path starts from Helyg on the
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 .
Though the summit, like that of many of the mountains in the Carneddau, is a flat, boulder-strewn plateau, the cliffs below the ridges are well-known rock climbs, notably
Ysgolion Duon (meaning ''black ladders'') and Craig yr Ysfa.
