Moderate sized quarry.*

Quarry site is largely overgrown with forest, but several buildings remain visible, including the Bwlch Gwyn farmhouse, which was repurposed during quarry operations. Outside the forested area are the abandoned terraces and chapel of the former quarry village of Rhiddolion.

Material was moved about 150 yards by tram to a water-powered mill. The quarry produced almost exclusively slab, carted by road to Betws y Coed. The quarry community outlasted the World War I closure; quarrymen found alternative work in Blaenau Ffestiniog, commuting via Pont y Pant station in the Lledr Valley.