Cadair Idris rises to 893 metres on the southern edge of the Snowdonia National Park, about 15 km south of Machynlleth. It is one of Wales's most dramatic mountains — not the highest, but arguably the most interesting in profile, with a distinctive flat summit ridge, a glacial lake (Llyn Cau) in a dramatic corrie on the southern face, and views that on clear days extend to Ireland.
Three main routes lead to the summit. The Minffordd Path from the south is the most dramatic, rising steeply through the corrie past Llyn Cau. The Pony Path from the north is the most gradual and the standard approach for less experienced walkers. All routes require a full day and appropriate clothing — conditions on the summit can be severe even in summer, and the mountain is frequently in cloud. There is a small visitor centre at Ty Nant on the northern side. Machynlleth is the closest town and a good base for an early start.