[1] After this failure the owning company was acquired by the owners of the neighbouring Oakeley quarry which was mining the north slopes of Allt-fawr.

The Oakeley manager proposed driving a tunnel from their upper quarry to meet the Nyth-y-Gigfran chambers and thus work the rock from the east.

[4] Between 1974 and 1997, the Gloddfa Ganol tourist attraction, based in Oakeley quarry, offered underground tours into the Nyth-y-Gigfran workings.

[1] The incline was unusual because it did not connect to the adits of the quarry; it stopped about 100 feet (30 m) below that level because the mountain was too steep above this point.

There, on a narrow platform built on the mountain slope, it was loaded onto slate waggons which were lowered to the Ffestiniog Railway.