Aaron Ralston, a 27-year-old mountain sports fanatic from Colorado in the United States, found himself in dire straits* alone in a canyon* in the desert when a 500kg rock came crashing down the canyon to smash his right hand and trap it against the canyon wall. A terrible accident, but the situation was made all the more serious because on this occasion Aaron had failed to tell anyone where he was going. At the last minute the plans for a trip with his climbing partners had fallen through, and on the spur of the moment he decided to head out on his own to cycle up a long mountain trail, leave his bike and then walk down the Blue John canyon. No one had the slightest idea where he was.
After three days of not seeing or hearing any sign of life Aaron realised he would die there if he didn't do something drastic. The course of action was horrific, but there was no other way. He would have to amputate his right hand. Fortunately he had a small multitool knife with him and he had some straps that he could use to make a tourniquet to stop himself bleeding to death when he cut the arteries. The knife had two blades. When he tried with the larger blade he found that it was too blunt to cut the skin.