The aerial photography , both historical and contemporary , is amazing. It alone is worth watching this movie for. Unfortunately that is really the only reason to watch the movie.
It is structured as two different stories with each tale being told alternately with the other. The stories don't really reinforce each other , however, and each time you leave one story to join the other the experience is about as seamless as a manual gear change without benefit of the clutch. If the filmmaker had constructed the movie as a two stories each told without interruption it might have worked. As it is it does feel overly long, which is a pity because the photography is fantastic.
Brilliant film: both in terms of the quality of the photography and the close filming of demanding ice climbing.