Here's a Vimeo movie by Nicholas Moreno showing his 24 day, 1100 mile tour along the Tibetan altiplano. Most of the trip was above 15,000 ft. This region contains the headwaters of three of the world's major rivers: the Yellow, the Yangtze, and the Mekong.
http://vimeo.com/42671681
http://vimeo.com/42671681