"The plain truth," the author Jon Krakauer wrote, "is that I knew better, but went to Everest anyway."
It was 1996. Krakauer, a correspondent for Outside magazine, was to hike to Mount Everest's base camp and write a story for the publication. Instead, he met the guides who helped pioneer the commercial climbing business on the world's highest peak, and convinced the magazine to let him climb to the top. His editors obliged.
By the end of his trip, eight climbers had died during a storm. At the time, it was the deadliest attempted ascent on the mountain. Eleven people have died on Everest this year, due in large part to the vast contingent of unqualified and unguided alpinists who now flock to the mountain during climbing season, the very phenomenon Krakauer went to document.
Three years before his trip, life on Everest changed, but to understand that, you have to understand the mountain's history.
British climbers made early attempts to reach the peak on the northern side of the summit in Tibet in the early 20th century. George Mallory and Andrew Irvine were spotted within hundreds of feet of the top in 1924, but the two never returned to camp to relay whether they'd made it. Mallory's body was found in 1999. Irvine's remains missing.
Sir Edmund Hillary and Sherpa guide Tenzing Norgay made the first official ascent in 1953 on the mountain's southern side, in Nepal. The first Americans summited in 1963. The group included Barry Bishop, who wrote about and photographed the trip for National Geographic.
But amid the Cold War, access to the mountain was severely restricted. China closed the Tibetan portion of Everest from 1950 to 1980. Nepal for years did not allow foreigners into the country to climb Everest unless they were accompanied by scientists, and when it finally opened its border in 1985, it issued one Everest permit per season per route.
By the 1990s, international tensions had eased and more qualified alpinists began showing up at the mountain, hoping to gain access to climb.
"Everest, you could always get a permit, but you had to be sponsored by your country's climbing agency," Todd Burleson, founder and president of guide service Alpine Ascents International, said in a phone interview. He's led two guided journeys to Everest's summit, and said aspiring climbers used to wait several years until their turn for a permit arrived.
"Up until about 1990, you'd take a group of the best climbers from your country to Everest and if one of those climbers got to the top, you were a national success," he said. "But during the '90s we learned a lot, and there were a lot of people who couldn't get on those groups who were very skilled. And then we started bringing them to the mountain."
Sensing opportunities for revenue and fresh off an economic modernisation, China began granting more permits. Then Nepal liberalised the permitting process, too, to keep up. Where fewer than 2,000 people attempted to climb the mountain in the 1980s, according to the Himalayan Database, nearly 4000 have tried each of the past two decades.
"In 1993 the world changed completely," said Eric Simonson, director at International Mountain Guides and a multiple-time Everest summiter.
Guiding agencies like Adventure Consultants and Mountain Madness, the subjects of Krakauer's 1997 book "Into Thin Air," began leading trips up Everest. Local Sherpas, who experienced mountaineers say are excellent climbers but sometimes unqualified guides, established companies that offered trips at less than half the cost, but not every agency did a thorough vetting of clients to see if they were physically capable of scaling Everest.
And so larger and larger crowds arrived at the mountain as the services at base camp improved, aided by technology and more precise weather tracking that allowed climbers to reach the peak in more predictably safe conditions.
But the cluster of people on the mountain is dangerous, too, sometimes preventing swift evacuations and cramming climbers together on perilous slopes.
By 1996, one of the world's most remote locales was becoming a tourist attraction. Krakauer, an avid climber, arrived to tell that story.
He summited the mountain on May 10, then returned to a forward base camp. As he descended, the weather turned, and dozens of climbers from three groups were stuck in a traffic jam and exposed to a hurricane-strength storm. So many climbers assaulted the summit at once - even after delays in securing ropes along the treacherous "death zone" some 26,000 feet in the air - they couldn't turn around in a timely fashion and retreat for cover.
Eight climbers died, including three guides.
"The commercialized trips and the overcrowding were what caused the tragedy [in 1996]," Hillary, who died in 2008, told Time magazine in 2003. "It was inevitable. I've been forecasting a disaster of that nature for some time. And it will happen again.
"You see, with so many climbers on the mountain, climbers are practically queuing up for the difficult parts. What happens then, quite a few don't get to the top till 3 or later in the afternoon. And then, like in this instance, the late weather comes sweeping in."
Krakauer wrote a 17,000-word article about the tragedy for Outside, then turned it into a book that made The New York Times bestseller list and was a finalist for the Pulitzer Prize. Sony bought its film rights nearly immediately after publication, and it was adapted into a TV movie ("Into Thin Air: Death on Everest") in 1997, and a feature film ("Everest") in 2015.
(Krakauer has criticized the 2015 movie for departing from actual events on the mountain. He told the Los Angeles Times it was "total bull." Director Baltasar Kormakur responded that his script was not based on the book.)
"I walked off of that mountain," said Burleson, who was awarded the American Alpine Club's most prestigious honor for his part in the 1996 rescue effort, "and I had phone calls from all over the world asking, 'Can I climb Everest? Can I climb Everest?' Before that, there were only a few of us and we knew what we were doing. But now everybody wanted to do it."
"The '96 tragedy, Jon Krakauer's book, the Mallory expedition [when Mallory's body was found in 1999], blogging, it crossed over from just climbers being interested to everybody being interested," Simonson said. "The audience exponentially increased."
The new demand for Everest expeditions outpaced the supply, especially from the mostly Western guide agencies that had offered such services, said Alan Arnette, an Everest expert, summit coach and blogger.
Those firms typically took small groups, often no more than 10 clients, and brought along up to four guides with several more Sherpas, who help fasten ropes and haul gear. Since acclimatising to Everest's elevation can take days, and the climbing is slow going, the average Everest quest takes close to two months and costs around $US70,000 ($A100,000).
Other guide agencies emerged and began leading larger trips at lower prices without requiring climbers to have certain requisite experience, experts say, and the mountain got even more crowded. And as more underqualified adventurers attempt to summit the peak, Everest was normalized as a tourist destination.
"If you have the money, you can go," Burleson said. "That's pretty much what's happened."
To Krakauer, who declined an interview for this story, the allure of climbing one of the world's most dangerous mountains has always defied logic.
"Attempting to climb Everest is an intrinsically irrational act - a triumph of desire over sensibility," he wrote in the introduction of "Into Thin Air. "Any person who would seriously consider it is almost by definition beyond the sway of a reasoned argument."
The Washington Post
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