Open working with mill.***

The workings spread across several levels, linked by short tramways and an incline leading to the mill area, where an arched tramway crossing survives. The mill site includes ruins of the mill, houses, a barracks and weighbridge, with launder pillars still standing and the line of the later turbine feed pipe visible on a former incline bed. The old tramway to the cart road now forms the path to Gladstone Rock. The main feature is the impressive exit tramway and its sequence of two steep inclines, reached by a half-mile descent on stone embankments and rock-cut terraces. The line crosses an earlier route from the Braich yr Oen copper mine, marked by the finest surviving stone-block sleepers in North Wales. Remains include drum houses, brakeman’s huts, bridge abutments, and at the foot of the lower incline, stables and sheds now incorporated into Hafod y Llan farm.

The quarry opened in the 1840s, first as a small slate working linked to the nearby metal mines, with a mill built early on and proposals for a rail outlet to Porthmadog. It expanded rapidly in the late 1860s, when the mill was enlarged, converted to turbine power, and the dramatic incline system was built in anticipation of a railway along Nant Gwynant. It became the most productive quarry in the Beddgelert district, yet still failed to justify its heavy investment and declined after the 1870s slump; only minor reworking took place in the 1960s.