Col-des-Roches Underground Mills

The valley at Le Locle has no surface river - the water drains into the limestone and runs underground - so from 1652 mill builders went after it where it was, cutting chambers into the rock at a natural swallow hole and installing waterwheels underground on several levels, one above another, driving mills, a sawmill and later an oil press. It is a genuinely unusual solution and among the few underground mill complexes in Europe. The works were abandoned in the nineteenth century, partly used as an abattoir, filled with rubbish, and then excavated and restored by volunteers from 1973. Visits are guided and descend through the chambers past the reconstructed wheels.

What you actually see

• Waterwheels inside a cave - stacked on levels in cut rock chambers.
• A valley with no surface river - the reason the mills went underground.
• Use from 1652 - mills, sawmill and oil press over two centuries.
• A volunteer excavation - dug out and restored from 1973.

When to go

All year, with reduced winter hours. Two hours.

Honest expectations

Visits are guided at set times, mostly in French. It is cool and damp underground with steps. Le Locle is a working watchmaking town, not a tourist one. Check opening before travelling.

Nearby

Le Locle and La Chaux-de-Fonds, both UNESCO watchmaking towns, are close.