While in summer the region of Ladakh is hospitable, green and lush, in winter it is almost totally cut off from the rest of the world. The mountain passes are usually closed by the snow and one of a few walkable ways to Zanskar Valley is the frozen river Zanskar that is often called 'Chadar' which means 'blanket'.
Locals wanting to get from Leh to Zanskar in winter have to walk on the river. This fast and powerful river that is confined in a steep canyon under a sheet of ice. It is also known as Chadar trek among trekkers from all over the world. It is one of the most challenging treks with a full length of around 100 kilometres.
There's a chance that the trek will loose its ambience because of the road that is being built between Leh and Zanskar so if you're keen to complete this challenge you should hurry up. And don't forget that a qualified guide is a must on Chadar since the trek is extreme and can be dangerous.