Moelwyn Mawr and Moelwyn Bach from Croesor

The walk starts from the National Park car park in Croesor. It follows the quarry track up the south side of Cwm Croesor to the ruins of Croesor Quarry, passes Llyn Croesor and crosses rough ground to the upper workings of Rhosydd Quarry. From there it climbs to Moel-yr-hydd, turns back west and goes up the north-east ridge of Moelwyn Mawr, at 770 m the highest of the group. The way on is down the rocky ridge of Craigysgafn to Bwlch Stwlan, above the reservoir of Llyn Stwlan, and up to Moelwyn Bach. A clear path runs down its long west ridge to a forest edge and a minor road, which leads back to Croesor.

It is 12.0 km with 842 m of ascent; allow about 6 hours. The grade is Hard, for the length, the climb and the rough, pathless stretches.

The quarry areas have many adits and unfenced chasms: keep to the path and stay out of the workings. Navigation skill is needed, especially in mist: the ground between the quarries is boggy and confusing, and the crags between the two Moelwyns need careful route-finding on loose scree.

The car park is free, with about 20 spaces, and Croesor is reached by narrow single-track lanes.

Route drawn by Global Adventurer along OpenStreetMap paths (© OpenStreetMap contributors, ODbL), with figures worked out from it. Check the forecast and the ground on the day: paths change.