These massive rock glaciers, also called stone flows, creep slowly downhill, driven by gravity.
Unlike ice glaciers, rock glaciers consist mainly of frozen rock detritus with ice in the cavities between. With the force of gravity these fascinating formations creep steadily downward, moving as much as a half a metre per year.
In summer the ice in the upper 1 to 2 metres of the rock glacier thaws. At this time of year, the noise of the meltwater can be heard not far below the surface.
The Chamanna Cluozza–Fuorcla Val Sassa–S-chanf walk leads past the nearly 2 km-long Val Sassa rock glacier.