The Siachen Glacier is located in the eastern Karakoram range in the Himalaya Mountains. At 76 km long, it is the longest glacier in the Karakoram and second-longest in the world’s non-polar areas.
The glacier’s region is the highest battleground on Earth, where Pakistan and India have fought intermittently since April 1984. Both countries maintain a permanent military presence in the region at a height of over 6,000 m (20,000 ft).

Source: http://en.wikipedia.org/wiki/Siachen_Glacier