Built between 1967 and 1972, the dam blends perfectly into its surrounding rocky landscape. Arriving by funicular (the world’s steepest), there is a fine view of the Mont Blanc massif. The 180m-high curved dam holds back 225 million m3 of water covering 327ha. In a geological paradox, the water here originates from the Mont Blanc massif on the other side of the valley; it gets here through underground galleries before rising thanks to a natural siphon phenomenon.