At the extreme corner of Switzerland (on the Swiss-French border) you will find the high valley of La Brévine; almost every Swiss child knows this name. Here, the temperatures dip to Siberian lows. But between spring and fall you will enjoy the mildest side of the Jurassic pastures: occasional farmsteads, the idyllic Lac des Taillères and the gently rolling wooded hills. The hike from La Brévine to the border town of Les Verrières opens up a melancholic, tranquil landscape of strange attractiveness.
If brooks and rivers run only sluggishly above ground, hydropower is nearly impossible to harness. That is why the inhabitants of the valley of Le Locle began to use subterranean streams. This is how the cave mills of "Col-des-Roches" arose.