Zemu glacier is situated in a large U-shaped valley at the base of the
Kanchenjunga massif in northwestern Sikkim. It has a length of about 26-km
and is the largest and the most famous glacier of the eastern Himalayas.
The Teesta River rises from the snout of this glacier.
Many tributary glaciers feed the trunk glacier. The side valleys, in which these glaciers lie, open into the main Zemu Valley from different directions. Icefalls and waterfalls have formed at the junction of the tributary glaciers with the Zemu glacier.