The mountain lies on main ridge of the Berwyns which runs north-south. The eastern side of the ridge is characterised by steep drops and crags including Craig Berwyn north of the summit and Craig y Llyn to the south. Craig y Llyn forms the headwall of a cwm, and it is to this that the word cadair (chair in Welsh) presumably refers. Further north along the ridge is Cadair Bronwen, whilst to south the ridge continues to Moel Sych (], meaning 'dry hill').