(CNN) He'd blacked out in the snow-swept night somewhere on Mt. Everest's airy northeast ridge. Now Kilian Jornet was lost, exhausted and delirious, whipped by a fierce wind in the "death zone" high above 8,000 meters (26,200 feet). The superstar Catalan climber had achieved a superhuman feat, scaling the world's highest mountain twice in six days without supplemental oxygen, both in breathtakingly fast times. But now, Jornet was teetering above the plunging precipice of the North Face with no idea how he got there or how to get to safety.
"I don't know if it was a dream or if it was real, I was sleepy," he says on his new film "Path to Everest." Daylight, he decided, would be his salvation and he hunkered into his green down suit to await a clearer view of his escape route back to the relative safety of the North Col. When news of Jornet's audacious double ascent pulsed around the world, his legend was complete. The first ascent in 26 hours in one continuous push from the Rongbuk Monastery base camp at 17,000 feet in Tibet was bionic. But twice? The second time in 17 hours from advanced base camp, which takes normal climbers four days? The feat is so jaw-dropping questions have been asked. But not for nothing is the celebrated ultra runner and ski mountaineer known as the "Extraterrestrial."
Jornet grew up with his mountain-guide father and outdoors-loving mother in a backcountry refuge in the Spanish Pyrenees. He climbed his first major summit at the age of three and got into endurance racing -- trail running in the summer, on skis in the winter -- as an exercise-obsessed teenager. He had a unique natural talent and surged to the top of the sport. By 25 he had achieved all the racing goals he thought would take him into his 40s, including multiple wins in Europe's Skyrunner World Series, the 106-mile Ultra Trail du Mont Blanc and Colorado's Hardrock 100. But he was burned out, and struggled with the expectation and exposure. "Somehow it's sad to reach your dreams," the 31-year-old told CNN.
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To refuel his motivation, he devised "Summits of My Life" -- a bold plan to set speed records up and down some of the most iconic peaks on the planet -- Mont Blanc, the Matterhorn, Elbrus, Aconcagua, Denali and Everest. He began in 2012, but the project got off to a tragic start when his friend Stephane Brosse was swept to his death by a collapsing cornice as they traversed Mont Blanc. The following year, Jornet scampered up and down Mont Blanc from Chamonix, France in a record four hours 57 minutes, and he added new marks on the Matterhorn (two hours 52 minutes from Cervinia, Italy) and Denali (11 hours 48 minutes). Weather scuppered his attempt on Elbrus, and while Argentina's Aconcagua was a success, it was a "complete disaster" in terms of acclimatisation and strategy, he says, after descending from the summit with jelly legs and mild altitude sickness.
Jornet arrived ready to try Everest in 2015 but instead threw himself into relief efforts for the devastating earthquake which had just rocked Nepal. He returned with another permit the following August, though it was the off season for climbing and the unfavorable conditions put paid to a summit bid. However, a solo acclimatization climb on near neighbour Changtse, a 7,543m (24,747ft) pyramid of rock, snow and ice connected to Everest by the North Col, provided him with what he says was the most powerful, life-affirming moment of the whole project.
"I was really pushing, feeling this kind of flow," he said. "Being at 8,000m completely alone and having the mountain to yourself and be playing there is really cool. I was applying all I had learned before and living every second. How you put your hands, how you put your feet -- the past and future don't exist, it's only the moment. It's a kind of meditation. It was beautiful to feel that small."
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When he and friends Sebastien Montaz-Rosset and Jordi Canals set foot on Everest itself they were caught in deep snow and worsening weather. Exposed on the northeast face, with avalanches sweeping over them, they only narrowly escaped. "We were really lucky to get down alive," says Jornet, who moved with girlfriend Emelie Forsberg to Norway to escape the crowds in Chamonix.
He returned to Everest again in spring 2017, accompanied by just Montaz-Rosset, Forsberg and a Nepali cook. He had acclimatized for more than 300 hours back in the Alps, climbing and staying in high mountain huts, and by hypoxic training on a bike -- using a mask to simulate the lack of oxygen in the air. His short expedition began with another training climb to near the summit of Cho Oyu, at 26,864 feet the world's sixth highest mountain. It was while on Cho Oyu he learned of the death of his friend Ueli Steck, the celebrated Swiss speed climber, in a solo fall on nearby Nuptse (25,791ft). Steck's death has made him more cautious, but he says: "Sometimes speed is safety. Risk is something that needs to balanced. You need to really know yourself, be humble about yourself and your capacities, and don't overestimate."
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Jornet's plan was to climb Everest unsupported and without supplemental oxygen from the northern side of the mountain in Tibet. After studying conditions, he settled on the "normal" route via the North Col and North East ridge, made famous by George Mallory and Andrew "Sandy" Irvine's tragic summit attempt in 1924. "What was cool was the challenge was to start from the last village and go to the summit," he says. He set out in the late evening of May 20 and made swift progress through advanced base camp (ABC) at 21,000 feet up onto the North Col at 23,000 feet where Montaz was waiting to film.
Climbing through camp two towards the "death zone" -- so-called because of its lack of oxygen and debilitating effect on the body -- Jornet began to experience stomach problems and slowed up. "I needed to stop and eat and have diarrhea," he says."But it was fun and always beautiful with great views." He battled onto the northeast ridge and pushed himself above 28,000 feet, scaling the three technical rock climbs without using the fixed ropes.
"Of course, when you are suffering it's not a pleasure moment but if you want to achieve something to see who you are, to explore yourself, you need to go close to your limits," he told CNN. "The satisfaction comes from the whole process, not just the results or the suffering itself." He reached the top minutes before midnight on May 21 after climbing for 26 hours. At the top he remembers seeing lights from parties setting out from the South Col in Nepal. "It was an incredible feeling to be for the first time on the summit of Everest in the middle of the night with no one around. It was a lifetime moment," he says on a video for watch sponsor Suunto.
Given no one had attempted to climb from Rongbuk straight to the summit before, Jornet established a fastest known time for the route. But his stomach issues had slowed him and his team were concerned. "I was really worried, it's hard to talk about," says a teary Forsberg in the film "Path to Everest." "For so many hours I thought something must have happened. It was really hard to try to keep the positivity." Given his health, he opted to stop at ABC on the way down. That was when he hatched his audacious dual summit plan. "I don't like being at base camp doing nothing so I thought it would be interesting to see if I was able to recover from one big effort and do another really close, to see how the body reacts," he said.
Five days later Jornet set off again towards the peak of the world. "The second time I was feeling better," he says. "I had no stomach problems and the weather was much nicer." However, his decision not to carry a radio meant Jornet was unaware the weather was worsening. As he climbed higher, the wind built into a frenzy. "Insane, insane," he shouts in "Path to Everest."
"Up there you cannot think a lot, everything is going slow in the brain," he told CNN. "The decisions are mostly like, 'Is this going to kill me?' If it's yes, you go down, if not you continue. In the mountains you need to be rational. Stress is just a waste of energy. The physical suffering is something you know will come so it's not really a question. You need to fight to survive. You can't abandon yourself because then you die." Exhausted, he reached Everest's peak after dark on May 27 in a time of 17 hours -- just 15 minutes slower than the fastest known time from ABC, set by Christian Stangl in 2006.
As moments go it was groundbreaking, and "opens up a new realm of possibilities in alpinism," he says. He turned around immediately, but after stumbling off route on his descent he waited until first light and used GPS coordinates on his watch to navigate his way off the North Face.
One Everest speed ascent without oxygen is impressive, two in six days is remarkable. Yet there were some who questioned the feat, both in terms of times and whether he had actually reached the top. One in-depth report ran to 75 pages, citing a lack of summit photos or video, discrepancies in his timings and inconsistencies in the GPS track logged by his watch. Jornet has since had his two ascents recorded in the Himalayan Database, a comprehensive log of all climbs in the region. "I believe that is important to give the maximum of information regarding our attempts in the mountains," he told CNN in a later email. "In this case, I've put at disposition everything I have and that I made following the way I want to approach mountains."
When Jornet began the Summits of My Life project he was still in the racing mindset, but as he went on it he says it became about something more existential. "On Everest the time was less important," he said. "It was more about the way to do it and was more about being more minimalistic. It was interesting to see how to approach mountains." Jornet is still setting records, though. This summer he broke the 35-year mark for the legendary Bob Graham Round, a 66-mile romp -- including a total vertical ascent of 8,200m (26,900 feet) -- up and down the 42 summits of England's Lake District in 12 hours 52 minutes.
But if he never won another race or set another record, you sense Jornet would still be content. "Training is every day," he says. "I could not race or do projects but I could not be not training, I like that more than winning."