The history of the Talyllyn Railway is inextricably tied up with the history of Bryneglwys slate quarry. All but invisible from the main valley road and from the present-day terminus of the Talyllyn Railway at Nant Gwernol, the quarry once employed 300 men and in its time produced 300,000 tons of slate and slabs. Bryneglwys lies on the same veins of slate as the quarries further east around Corris and Aberllefenni. Slate was first quarried at Bryneglwys in the 1840s, by John Pughe of Aberdyfi, the end product being carried to Aberdyfi by pack animals or on carts or sledges for onward shipment by sea.