Riverboarding Of Great Aletsch Glacier, Bernese Alps, Valais, Switzerland

During the last glacial periods, the Aletsch Glacier was much larger than now. 18,000 years ago the lower part of the ridge, between Riederalp and the glacier, was completely covered by ice. Only the summits of the Bettmerhorn, Eggishorn and the Fusshörner were above the glacier. After an important retreat, the glacier again advanced 11,000 years ago during the last glacial period. The glacier reached the Rhone valley, and its ice the Riederfurka. Remaining moraines are still visible in the Aletsch Forest.
Since the last glaciation, the glacier generally retreated. However slight climatic changes happened and, in 1860, the glacier was 3 km longer and the ice level 200 m higher.
As for many other glaciers, records show a major longer-term retreat trend. The Aletsch Glacier receded by 100 m (330 ft) between 2005 and 2006.