A grass gully separates our arête from a few rocks nearer Dyrysgol, which are of basaltic character and rather interesting to descend.
Cader Idris.—The name ('Chair of Idris') includes the whole mountain range, some 7 miles long, that separates the Mawddach from the Dysynni. It is a continuation of the outcrop of volcanic trap rock that stretches from the Arans down to Cardigan Bay, and, as usual with such mountains, its volcanic origin has had much to do with its grand scenery.
The range runs in an E.N.E. direction from the sea south of Barmouth, and reaches its greatest elevation at Pen y Gader (2,929 ft.) It forms two other noteworthy peaks on the chain, Tyrran Mawr (2,600 ft.), 2 miles to the south-west, and Mynydd Moel (2,800 ft.), 1½ mile to the north-east.
The north side presents a fairly even front of precipitous rock for 3½ miles. Near the highest point, however, a huge amphitheatre of rock, a thousand feet in height, suggesting a volcanic crater half fallen away, breaks the continuity of the ridge, and contributes the finest bit of mountain scenery that this side of Cader can offer. Probably this hollow suggested first the name of 'Cader,' though there is a recess on the summit ridge that is usually taken to be the seat in question.
But the mountain can show something even better on the south side. Its high dependency Mynydd Pencoed joins the main ridge almost at the summit of Pen y Gader, and its extremity Craig y Cae forms with Cader itself another crater-like hollow, which, with Llyn y Cae lying at the foot of the crags, is even wilder and more magnificent than the one on the north side. Excepting the crags in this cwm the south side of Cader consists of steep grass slopes, and the general aspect of the mountain is uninteresting.
An account is published in the Gentleman's Magazine (vol. xxxviii. p. 147) of an ascent of the mountain in 1767 by L. N.
Cader Idris was also climbed in 1863 by Prince Arthur.
Several members of the Alpine Club worked their way up the direct route from Llyn y Gader in 1881, and there is some mention in the Alpine Journal (vol. xii.) of a few ascents by Mr. H. Willink.
The gullies along the north face of the mountain were explored for many years by F. H. B.