Everest—and how old is it

Mount Everest—known in Nepali as Sagarmatha and Tibetan as Chomolungma—straddles the border between Nepal and Tibet at the crest of the Himalayan mountain chain. Although reaching the top of the world is an arduous and potentially deadly undertaking due to the extreme altitude, avalanches, icefalls, and other hazards, the mountain lies quite close to the equator, at a latitude of approximately 28 degrees, the same as Tampa, Florida. Earth scientists estimate that Everest is 50 to 60 million years old, a youngster by geological standards. The mountain was formed by the upward force generated when the Indian and Eurasian tectonic plates collided, pushing up the rocks that formed the highest mountain on Earth. That force is still at work today, pushing Everest’s summit about a quarter of an inch higher each year.

The hazards of climbing Everest

At 29,032 feet, Everest’s summit has approximately one-third the air pressure that exists at sea level, which significantly reduces a climber's ability to breathe in enough oxygen. Because of this, scientists have determined that the human body is not capable of remaining indefinitely above 19,000 feet. As climbers move higher up the mountain and their oxygen intake is reduced, their bodies are increasingly at risk for a number of ailments, including pulmonary edema, cerebral edema, and blood embolisms. The chances of frostbite are also dramatically increased at such altitude as the heart works harder to pump blood around the body delivering oxygen. The life-giving organs are first priority; digits are last.

Many routes are there to the top

Although 17 different routes have been pioneered to the summit of Everest, almost everyone climbs it via one of two routes. From Nepal there’s the Southeast Ridge, the line created by Tenzing Norgay and Edmund Hilary in 1953. From Tibet, there’s the North Ridge, where George Mallory disappeared in 1924 long before a Chinese team finally completed the climb in 1960. Although experienced mountaineers say the overall difficulty of the two routes is comparable, the challenges are different. On the Southeast Ridge, mountaineers must race through the hazardous Khumbu Icefall, but it’s a slightly shorter summit day and easier to descend quickly in the event of an emergency. On the North Ridge, it’s possible to drive jeeps all the way to base camp, but mountaineers must traverse several kilometers of terrain above 27,000 feet to reach the summit. (Read about China's highway to Everest.)

Everest's guides

For local logistics companies and the government of Nepal, Everest is big business. A typical spot on a commercial team costs anywhere from $40,000 to $100,000 depending on the level of service and the expertise of the outfitter. The Ministry of Tourism reported collecting $5.2 million in 2018 permit fees. The industry is built on the backs of a small cadre of professional Nepalese guides who work together each spring to prepare the route with fixed ropes and ladders, stock each camp with essentials like tents, stoves, bottled oxygen, and food, and then patiently coach their foreign guests up to the summit.