Cader Idris

Cader Idris rises to 893 metres at Penygadair, the highest point of the mountain. Its signature scene is Cwm Cau, a near-circular glacial corrie holding Llyn Cau. The cliffs, rough summit rocks and lake make this feel different from a simple rounded hilltop. On a clear day, the high ground opens views across Tal-y-llyn, the southern Eryri ranges and toward the coast.

The mountain is also a good place to notice geology rather than just scenery. Ice shaped the corrie during the last glaciations, while the mountain's Ordovician sedimentary and igneous rocks show through on the climb. The Welsh name means Idris's Chair, tied to old giant and prince legends.

Cader Idris is a full mountain outing, not a drive-up viewpoint. The most useful starting point for visitors is Dôl Idris car park, on the B4405 off the A487 south of Dolgellau.

These times are planning estimates, not promises. The paths are rough and steep in places, and high-level navigation matters, especially in cloud.

• Minffordd Path: 9 km there and back, about 788 metres of ascent, and roughly 5 to 6 hours. It is hard/strenuous and passes through the gorge and the dramatic Cwm Cau/Llyn Cau bowl.
• Pony Path from Tŷ Nant: about 10 km there and back and roughly 5 hours. It climbs the northern side and is often the most popular approach.
• Llanfihangel y Pennant: about 16 km there and back and around 7 hours. It is longer and quieter, with a more gradual feel overall.

Expect exposed, uneven ground and no services at the summit. A small stone shelter sits close to Penygadair and can give brief relief from wind or rain, but it is not a substitute for warm layers or a reliable weather plan. The temperature at the top can be several degrees lower than at Dôl Idris, and low cloud can arrive quickly.

The reserve supports peregrine falcons above high crags and ring ouzels in rocky ravines. In summer, look for arctic-alpine plants on the cliffs and listen for mountain and woodland birds lower down. Keep to durable paths, avoid disturbing wildlife and take all litter back down.