An astonishing world record was set earlier this month in Nepal after a climber named Tashi Gyalzen Sherpa climbed to the summit of Mount Everest a record-breaking four times in just fifteen days, accomplishing a feet of physical and mental endurance unparalleled in the history of mountaineering.

It would be difficult to overstate just how impressive Sherpa's feat was. Ascending 29,032 feet to the height of the towering mountain, where the oxygen is gaspingly thin and the weather perilously treacherous is, for many, the highlight of their climbing lives. To go up and down repeatedly, allowing one's body to adjust to the difference in oxygen at various levels, is almost incomprehensible. Yet the 29-year-old, who hails from a small Nepali town called Phortse, managed to achieve what seemed unachievable.

Tashi started working as a climbing guide in 2017. Two years later, in 2019, he ascended to Everest's summit for the first time. In the years since, he reached the peak four times: three from the Nepal side, and once from the Tibetan side. This year, things were different. His first ascent occurred on May 9, when he was part of a rope-fixing team laying the route for the 8K Expedition. After that, Tashi quickly went up a second time (in reflecting, he told reporters that the second climb was the easiest).

Finally, after ascending a third time while assisting a client, Tashi quickly scaled the mountain solo for his fourth climb. As he later recounted, "I made to the top of Everest along with my client. I brought him back safely to the Everest Base Camp and then immediately started for my fourth summit the same night. My fourth summit attempt started from Base Camp on 22 May with an aim to reach the summit on May 23, and I was alone during my final push to the summit. There were no fellow Sherpas along with me. I carried all the required oxygen and necessities. I started for the summit on 8:00 pm (local time) on 22 May from Camp IV."

Tashi's remarkable achievement comes during a time of many record-breaking feats on Everest. Last season, a climber named Dawa Phinjhok Sherpa achieved the summit three times in just eight days, and photojournalist Purnima Shrestha made headlines for achieving the summit three times during the season.

“Tashi represents a new generation of Sherpa climbers—guides, record-breakers, storytellers, and trailblazers,” says mountaineering expert Ang Tshiring Sherpa. “They are climbing in the era of technological advancement. The world is now connected through smart devices, which, among other things, has even made Everest climbs faster.” Nepal is home to eight of the world's 10 highest peaks and welcomes hundreds of climbers each spring, when temperatures are warmer and winds are typically calmer.

Senior writer Chris DeWeese edits Morning Brief, The Weather Channel’s newsletter.