Aletsch Glacier

The Aletsch Glacier (Aletschgletscher, ˈalɛtʃˌɡlɛtʃɐ) or Great Aletsch Glacier (Grosser Aletschgletscher) is the largest glacier in the Alps. It has a length of about (2014), has about a volume of (2011), and covers about (2011) in the eastern Bernese Alps in the Swiss canton of Valais. The Aletsch Glacier is composed of four smaller glaciers converging at Konkordiaplatz, where its thickness was measured by the ETH to be still near . It then continues towards the Rhône valley before giving birth to the Massa. The Aletsch Glacier is – like most glaciers in the world today – a retreating glacier. As of 2016, since 1980 it lost of its length, since 1870 , and lost also more than of its thickness. The whole area, including other glaciers is part of the Jungfrau-Aletsch Protected Area, which was declared a UNESCO World Heritage Site in 2001. The Aletsch Glacier is one of the many glaciers located between the cantons of Bern and Valais on the Bernese Alps located east of the Gemmi Pass. The whole area is considered to be the largest glaciated area in western Eurasia. The Fiescher and Aar Glaciers lying on the east have similar extensions. Except the Finsteraarhorn, all the highest summits of the Bernese Alps are located within the drainage basin of the glacier. The Jungfrau and Mönch constitute the northern boundary; the Gross Fiescherhorn and Gross Wannenhorn lie on its east side; finally the culminating point, the Aletschhorn () is located on the west side. Before reaching the maximum flow, four smaller glaciers converge at Konkordiaplatz: From the western mouth flows the Grosser Aletschfirn, which runs along the northern foot of the Aletschhorn and Dreieckhorn. The Grosser Aletschfirn is supplied from the north by three notable firns: the Äbeni Flue-Firn, the Gletscherhornfirn, and the Kranzbergfirn. All of these firns have their starting points at around . From the Äbeni Flue-Firn to the Konkordiaplatz, the Grosser Aletschfirn is long and is on average about wide.