While hiking through the desert in Arizona, Zak Anderegg found a puppy in a 350-foot deep Canyon (100m) and decided to go back with equipment to rescue the poor dog.
 

Canadian freeride mountain biker Geoff Gulevich's impressive downhill canyon run at the 2013 Red Bull Rampage challenge in Virgin, Utah.
 

Scotty Bob flew through a very narrow canyon (the Beehive line) in Utah and this is what he filmed via his helmet cam.

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Crazy wingsuit proximity flight

‘You can trust me, honey’