Historian Walt Unsworth once said, "Had Mount Everest been climbed at the first attempt, the achievement would have been hailed as notable and then quickly forgotten. It was, ironically, repeated failures which gave the mountain real stature."
A climber uses a ladder to cross a crevasse at Everest's Khumbu Icefall, not far above base camp. Shifting ice exposes new crevasses with little warning, making the Khumbu Icefall the most dangerous section of a southern Everest ascent.

