The description doesn't make it sound too bad, does it:
Mountain race, with numerous passages in high altitude (>2500m), in difficult weather conditions (night, wind, cold, rain or snow), that needs a very good training, adapted equipment and a real capacity of personal autonomy.
Then you see this:
... then this:
... and then this ... HARDCORE!!
:
http://utmbmontblanc.com/en/
Mountain race, with numerous passages in high altitude (>2500m), in difficult weather conditions (night, wind, cold, rain or snow), that needs a very good training, adapted equipment and a real capacity of personal autonomy.
Then you see this:
... then this:

... and then this ... HARDCORE!!

View: https://www.youtube.com/watch?v=gsxnOfw_b1Q
http://utmbmontblanc.com/en/