After Hiker, 17, Suffered ‘Hallucinations’ in Mt. Everest’s ‘Death Zone,’ She Was Forced to Make a Heartbreaking Decision (Exclusive)

As a little girl, Bianca Adler would sit cross-legged on the floor, flipping through her family’s picture books of Mount Everest — mesmerized by the snow-dusted peaks and climbers standing at the top of the world.

“I remember thinking, ‘Wow, this is beautiful,’ ” she recalls to PEOPLE.

Her fascination was fueled by her parents’ expeditions to Everest in 2006 and 2007. Adventure, it seemed, was in her blood.

Raised in Melbourne, Australia, and later in the French Alps, Adler grew up surrounded by mountains and parents who believed in the transformative power of the outdoors. “I was always asking my dad to take me on bigger, harder climbs,” she says. “He never pushed me into anything dangerous, it was always my choice. I just loved it.”

By 12, she climbed Mont Blanc. Two years later, she summited Aconcagua, one of the youngest ever to do so. Over the next years, she tackled dozens of 4,000- and 6,000-meter peaks in the Alps and Nepal, culminating in Mt. Manaslu (8,163 meters), where she became the youngest woman ever to summit.

Each climb taught endurance, discipline and mental toughness. “We’d do 6-8 day hikes in the Australian Alps, hiking 25-30 km per day and rationing food and water,” she says.

Eventually, her years of training led to the moment she had been waiting for: Everest. Preparation began more than a year in advance, with early mornings spent running, cycling and on the StairMaster, combined with climbing-specific strength training.

Her father trained alongside her, her mother often joined in, but Adler knew motivation had to come from within.

“There were definitely moments I doubted myself,” she admits. “Physically, women aren’t as strong as men, and Everest is the same mountain for both. But then I’d remember all the mountains I’d already climbed.”

To stay motivated, she recorded short clips during workouts and expeditions. “When I didn’t feel like going to the gym, I’d rewatch those videos — me exhausted, saying, ‘This is why you need to train, because this is how hard it gets,’ ” she says, laughing.

“I trained very hard for all of these peaks and continued my training for Everest,” she adds. “I did 5-6 days a week of long cardio sessions on the StairMaster and spin bike, plus climbing-specific strength training.”

In late March, Adler, her father, and a small group of friends and family set out for Nepal. After a 10-day trek through rhododendron forests and Sherpa villages, they finally arrived at Base Camp, perched at 17,000 feet.

Reaching Base Camp is just the beginning of a complex Everest expedition, which involves meticulous preparation, logistics and significant expense.

“Costs vary widely depending on whether climbers use local or Western companies, hire individual guides and pay the Nepalese government’s peak fee,” Adler explains.

Once on the mountain, life is both breathtaking and grueling. The thin air makes even eating exhausting, meals are simple — often pasta with tuna or potatoes — and staying hydrated is essential. The mountain also presents unusual challenges, including something most people don’t think about: toilets.

“At Base Camp and Camp Two, there’s a small tent with a barrel to squat over. Up higher, we carry ‘wag bags,’ plastic bags we have to use and carry down,” she says. “It’s a recent rule to reduce human waste damage on the mountain.”

Waste management has improved dramatically in recent years. “Nepal now enforces stricter rules, and huge drones are even used to airlift trash from higher camps,” she says. “Personally, I try my best to leave no trace — everything I bring, from food wrappers to oxygen bottles, comes back down with me.”

After a week of acclimatization, her family and friends descended, leaving Adler and her father to begin their climb.

Their ascent followed a series of rotations — Base Camp to Camp One, Camp Two, Camp Three, then back down — a rhythm designed to help their bodies adapt to the thin air. Before the final push, they participated in a Buddhist Pooja ceremony led by Sherpas.

“It’s a tradition to ask the mountain for permission and protection,” Adler explains. “I still wear the string they gave me; it’s a reminder of respect and safety.”

The four-day climb toward the summit was grueling, with glaciers bridged by ladders, deep crevasses to navigate, and air that seemed to vanish with every step. “Once we reach Camp Three, we start using bottled oxygen,” she says. “Even then, it feels like you can’t breathe. We’d walk maybe seven steps a minute before stopping to catch our breath.”

Midway through the ascent, her father fell ill and had to remain at Camp Two. It was a devastating setback, but Adler’s determination only strengthened.

Pressing on with two Sherpa guides, she reached Camp Three, rested overnight, and then climbed to Camp Four — the final stop before the summit.

With the top still hours away, Adler knew she was entering the “death zone,” the perilous region above 8,000 meters where humans cannot survive for long. She planned to leave at 6:30 p.m., climbing through the night while carefully conserving her energy.

When she stepped out of her tent, horizontal winds and temperatures between –20 and –30 °C hit instantly. From Base Camp, her mother monitored multiple weather models, predicting the winds would ease after a few hours, but for now, the conditions were brutal.

“There’s wind blowing snow everywhere. It’s pitch black. Ice was forming on my eyelashes, and I had to melt it with my thumbs,” Adler recalls. “But mentally, I was strong. I thought, This is my dream — I’m climbing Everest.”

After seven hours of climbing through the darkness, she reached the Balcony at 8,400 meters — just 400 meters shy of the summit. But as the weather worsened, her hands and toes began to go numb, early signs of frostbite. Many climbers were already turning back. She radioed her father and made the hardest decision of her life: to retreat.

“I realized I couldn’t risk my hands, my toes, or my life for the summit,” she says. “Even with so little oxygen and some hallucinations, I knew I wanted to keep climbing for the rest of my life. One summit wasn’t worth losing that.”

Back at Camp Four, Adler spent nearly four days in the death zone — far longer than most climbers. “It’s horrible on your body to stay that long where oxygen is so scarce,” she says. “Even simple movement feels impossible. My lungs were struggling, and my face was burned and dark from the constant snow and wind; it wasn’t frostbite, but it left its mark.”

During that quiet, grueling stretch, she filmed a video to process what she was living through, footage that would later go viral on TikTok.

That evening, she attempted another push toward the summit but turned back again, completely spent. “I didn’t reach the summit this time,” she says. “But I came closer than most people ever will. And I learned something even more important than standing at the top — how to listen to my body, make hard choices and respect the mountain.”

“Sometimes the bravest thing you can do,” she adds, “is turn around.”

Eventually, Adler reunited with her father at Camp Two, where he was still recovering. Together, they descended to Base Camp, where her mother was waiting.

“Almost no one stays that long in the death zone,” she says. “Even the Sherpas with me, who had been on Everest many times, had never done anything like this.”

The toll was severe: she’d lost weight and muscle mass, and her lungs took weeks to recover. “I looked and felt pretty bad,” she admits. “But once we flew from Base Camp to Kathmandu — at a lower altitude — everything started working better again.”

Back home, healthy and back to her normal weight, Adler began sharing her experiences online. She posted clips from the climb on TikTok and Instagram — including the one filmed in the death zone after her first summit attempt. To her surprise, it went viral, reaching 73 million people.

“At first, I was just shocked by how much attention it got,” she says. “I’d never really received negativity online before, and suddenly there were people questioning everything. But that quickly shifted once I saw the response from so many others.”

“I really had a positive experience on Everest,” she continues. “A lot of people only see the viral videos and make assumptions about the expedition. Of course, there were challenges, but overall it was incredible. I love a challenge, and even when it was hard, I was enjoying it.”

Many of the messages she received came from young women inspired to take their first hiking or mountaineering courses.

“That made it all worth it,” Adler says. “I wanted to share photos and videos from the climb to encourage people — especially girls — to dream big, take on challenges and set goals for themselves. It doesn’t have to be Everest. It could be getting outside, hiking or trying something completely new. Nature has so much to teach you.”

Now back in school, Adler is already planning her next adventures — including other 8,000-meter peaks like K2 and new climbs in South America and the Alps. “My climbing definitely doesn’t end at Everest,” she says.

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The experience, she adds, gave her a deeper understanding of her own strength, both physical and mental. Her thoughts drift back to the little girl in Melbourne, cross-legged on the floor, staring at picture books of Everest.

“It feels surreal,” she says softly. “I grew up dreaming about this mountain, and now I’ve lived it — the cold, the wind, the struggle, the beauty. One day I’ll reach the summit. But for now, just being on Everest, experiencing it, surviving it — that’s enough.”