The Fiescher Glacier (Fieschergletscher in German) is a valley glacier on the south side of the Bernese Alps in the canton of Valais , Switzerland . 16 km (9.9 mi) in length, it is the second longest glacier in the Alps. The glacier covers an area of 33 km2 (13 sq mi).

The starting point of the Fiescher Glacier is 4,000 m (13,000 ft) above sea level, on the eastern slope of the Fiescherhorn, it is flanked to the west by the Grünhorn and Gross Wannenhorn and to the east by the Finsteraarhorn .

In the lower section, the Fiescher Glacier flows south through a deep valley between the Gross Wannenhorn and the Wasenhorn. In summer, when the snow layer melts, it has a grey colour as it is covered with rocks coming from the steep slopes of the mountains around.