Mount Everest is the highest mountain in the world. Its elevation of 29,035 feet (8,850 meters) was determined using GPS satellite equipment on May 5, 1999. It was previously believed to be slightly lower (29,028 feet /8,848 meters), as determined in 1954 by averaging measurements from various sites around the mountain. The new elevation has been confirmed by the National Geographic Society (See the National Geographic Society's Mount Everest site for more information).

The first seven attempts on Everest, starting with a reconnaissance in 1921, approached the mountain from Tibet, where a route to the summit via the North Col and North Ridge seemed possible. All were unsuccessful. George Mallory, who spearheaded the first three expeditions, lost his life with Andrew Irvine during a failed ascent in 1924. Unsuccessful attempts continued through 1938, then halted during World War II. By the war's end, Tibet had closed its borders, and Nepal, previously inaccessible, had done the opposite. Starting in 1951, expeditions from Nepal grew closer and closer to the summit, via the Khumbu Icefall, the Western Cwm, over the Geneva Spur to the South Col, and up the Southeast Ridge. In 1953 Edmond Hillary and Tenzing Norgay reached the summit.