This amazing footage was shot when Reinhold Messner and Peter Habeler made their epochal ascent of Everest without oxygen in 1978.
The pair were climbing Alpine style as part of a larger expedition, and the ascent was not without drama.
Messner became snowblind and disorientated on the descent and was lucky to make it back.
Read about how you can avoid a similar problem in the Mountain Genius section of July’s Trail – out now!
Scroll down to take a look...