Guy Cotter: 'Mount Everest is my church, my temple'

New Zealand mountaineer Guy Cotter has summited Mount Everest five times and scaled 7 of the world's 14 above-8000m peaks. For over 30 years, he has led guided Everest expeditions with Adventure Consultants - a company set up by his mentors Gary Ball and Rob Hall, who died on two separate climbing expeditions in the '90s. In the new book Everest Mountain Guide, Cotter describes what actually goes on during an Everest expedition and also traces the evolution of high-altitude guided mountaineering.