Barrage de Mauvoisin tunnels

Day 7 of the Classic Haute Route - climbed to the Col des Otannes, then descended the Pierre a Vire to Lac de Mauvoisin, from where we ascended to the Chanrion Hut (2462m), one of the older refuges but very cosy.

A wet and cloudy day with a l o n g descent to the valley and then walk up again into the hills. However the ascent inside the Mauvoisin dam made up for this with atmospheric walks across the top in the fog. The tunnels in the picture were made to support the construction in the 1950s and are the more impressive for it.