The slate quarries
The intensive exploitation of the Slate Quarries lasted from 1878 until the First World War.
On Malansac, four shafts were dug and on Pluherlin, perpendicular to the river, a whole network of galleries were built in the rock. The quarries occupied up to 300 workers!
On the surface, what is called the querningallows to divide the blocks from 6 to 8 cm thick. Then splitters reduce them in thickness with thin steel scissors. Finally, the cutters complete the work with a square, giving the desired format.
Slate is very present in the local habitat: low walls, roofing slates, fence posts… Today, Les Grées is a protected area because rare species of bats live there.
The former quarries are prohibited to the public for safety reasons.