Torrent des Ruines

The toponym “les Ruines” is common in the Alps, often referring to unstable terrain that suffers heavy erosion and torrential flooding: lava, a mixture of water, earth and blocks of stone. The floods move at speed (at tens of km/h) in a very straight, steep channel, but behave like a drift that can transport blocks several cubic meters in size (the equivalent of a car or even a van) just like volcanic lava.