Cwmorthin Slate Quarry

Wear sturdy footwear and bring waterproofs, a warm layer, water and an offline map. Wet slate is slippery, the ground around the workings is rough, and the ruins, shafts and adits can be unstable. Do not enter mine workings or climb on structures. Stay on obvious open paths, respect gates and private land, and treat the lake and quarry edges with care. A dry, clear day gives the best footing and mountain views; early morning or late afternoon usually brings softer light across the slate and a better chance of having the valley to yourself.

The usual start is the small car park at the end of Cwmorthin Road, reached from Tanygrisiau near the Ffestiniog Power Station. From the gate, the path rises steeply on loose, uneven slate. It is a short approach to the lake, but exploring both sides and the quarry ruins turns it into a several-hour walk. The little car park fills quickly, especially on weekends, so an early or weekday start is the least frustrating option. Do not rely on facilities or refreshments at the quarry.