K2 (8611m) is the second-highest mountain on Earth. It is located in the Karakorum segment of the Himalayan range, on the border between the Gilgit- Baltistan region of Pakistan administered Northern Areas and the Taxkorgan Tajik Autonomous County of Xinjiang, China. However, those who climb K2 8611m must acquire entry via Pakistan as the Chinese side is inaccessible.
There are a number of routes on K2. First is the extremely high altitude and resulting lack of oxygen. There is only one third as much oxygen available to a climber on the summit of K2 as there is at sea level. Second is the propensity of the mountain to extreme storms of several days’ duration, which have resulted in many of the deaths on the peak. The third is the steep, exposed, and committing nature of all routes on the mountain, which makes the retreat more difficult, especially during a storm. Despite many tries, there has been no successful ascent during the winter.