The Corris quarries are the most southerly of the North Wales slate quarries. At their peak they employed 800, but today only a handful remain. They only produced around 20,000 tons of the 350,000 tons produced by North Wales quarries at their peak.
Quarrying started in the Corris area in 1810 though there is some evidence that it began in Aberllefenni in 1500. The numerous quarries were at their most productive between 1850 and 1900. Initially the slate was carried by horse and cart, then transported by boat. To expedite the export of slate, the Corris Railway was built in the 1850s and from then on slate was transported to Machynlleth. The Talyllyn Railway was completed in 1865.
The quarries in the area in more detail are
Bryneglwys the largest producer with around 30% of the Corris total production.