Wikipedia
Trümmelbach
The Trümmelbach Falls (In German: Trümmelbachfälle) in Switzerland are a series of ten glacier-waterfalls inside the mountain made accessible by tunnel-lift and illuminated.
The Trümmelbach alone drains the mighty glacier defiles of Eiger (3970 m), Mönch (4099 m) and Jungfrau (4158 m) and carries 20,200 tons of boulder detritus per year.
Its drainage area is 24 km², half of it covered by snow and glaciers. The falls carry up to 20,000 litres of water per second.