Witness the power of water, carrying boulders of all sizes in this impressive video filmed at the Illgraben-Bhutan Bridge, in Switzerland. The cause of this flash flood phenomenon is the massive erosion, which apparently is getting bigger every year and has become a tourist attraction. This video is from the last flash flood.
Erosion caused the mountain to collapse and the vast, pale yellow and reddish rock basin to form, which becomes bigger every year. From the Grabenrad or the Illhorn (2,716 m) there are "fear inspiring" yet stunning views down into the Rhone valley.
This is another video from 2011:
It looks like mother earth ate Mexican last night, as some people said in the YouTube comments.