This walk starts at the Minffordd car park on the main A487 trunk road several miles south of Dolgellau. The car park is situated on the west side of the road just by the junction with the minor B4405 road to Tal-y-llyn at grid reference SH732115. Use OS map OL23 and take waterproof clothing. It is a moderate 6-mile walk which will take approximately 4 hours.
From the car park head up the tree lined track that crosses the Afon Fawnog. The track then bends left and passes the old National Trust building at Dol-y-cae. Shortly after the building the path crosses the Nant Cadair then turns right and heads north on its steep and rocky ascent through the woodland. The path eventually comes out above the woodland and reaches the open valley. Here it splits but continue along the main path heading north then north west in to the Nant Cadair valley. The path bends left and heads west through the Nant Cadair valley and eventually to the shores of Llyn Cau in Cwm Cau. From Llyn Cau a very steep path heads south up on to the rim of the cwm. Once at the top, follow the path and head west along the back and then the crest of the rim ridge. The path will turn right and head north to reach the small summit at the top of the Craig Cwm Amarch ridge which heads south west from the summit. From the summit of Craig Cwm Amarch head north towards the col at Craig Cau.
From the col at Craig Cau ascend north for two hundred metres then ascend north east over the rocky boulder field for four hundred metres and you will reach Penygadair the highest summit of Cadair Idris where there is a small hut.
From the hut head north east to east along a wide grassy ridge towards Mynydd Moel. After just over a kilometre and a half along the grassy ridge, crossing two small summits, you will ascend to the top of Mynydd Moel. From the summit of Mynydd Moel descend south to south east on fairly pathless terrain. Turn south after a while and then cross the stile to reach a more obvious path. The path continues its steep descent south hand railing a stone wall which it eventually crosses and then heads south west.
After just under another half a kilometer of descent the path will eventually reach the wooden bridge over the Nant Cadair that you saw earlier above the woodland. Cross the wooden footbridge and turn left. Trace your footsteps back down the steep woodland path to Dol-y-cae and follow the track back to the car park.