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Free solo -

Free soloing is a type of climbing that involves no ropes or safety equipment. The climbers has nothing but their bodies to make their way up the side of the mountain and keep them there.

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Free solo -

It’s one of the most dangerous sports in the world. Research is being done on some of the best free solo climbers to determine if their brains function in a way that makes them feel less fear than the average person.

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Free solo -

Many free solo climbers have died in horrific falls. Even the most skilled climber is capable of a momentary lapse in concentration or slip of the hand that will send them free falling to their death.

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Alex Honnold -

Free solo legend Alex Honnold is one of the few climbers whose feats are known outside of the climbing community. The missions he undertook were assumed to be humanly impossible.

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'Free Solo' (2018) -

His success was immortalized in the Oscar-winning documentary ‘Free Solo.’ This introduced the world to the insane concept of free solo climbing, as well as showing that the human body is capable of incredible things.

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Half Dome -

Honnold’s first history-making free solo climb was in 2008. He tackled the 2,000 ft (610 meter) wall of Half Dome in the Yosemite Valley. If he fell from that height, it would take 10 full seconds before he hit the ground. That’s a lot of time to think!

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Half Dome -

This wall had never been free soloed before, and it shocked the climbing world to know that it could be done. He completely changed the realm of possibility.

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El Capitan -

However, Honnold wasn’t satisfied. He felt that he’d gotten lucky with his Half Dome climb. He wanted to truly master the art of the free solo. This started him on his seven year journey to conquer El Capitan.

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El Capitan -

El Capitan is an iconic 3,000 ft (915 meter) wall that dominates Yosemite National Park. It’s considered an extremely dangerous climb with ropes, but the idea of free soloing that face was inconceivable. Even the most daring record-breaking climbers thought he was insane.

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First attempt -

Honnold trained meticulously for years, memorizing each of the thousands of tiny holds he would need to find and careful movements he would need to make. In 2016, he made his first real attempt, but quit after an hour when it didn’t feel right.

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Second attempt -

On June 3, 2017, Honnold woke up before dawn in the van he called home, parked in Yosemite National Park. He had his usual breakfast and made his way to the wall with nothing but a pair of climbing shoes and a bag of chalk to keep his hands dry. The moment was right and he began his ascent to history.

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Success! -

The climb took three hours and 56 minutes, and according to Honnold it felt perfect. His years of training paid off and he moved up the sheer cliff face with ease. At many points the ridges barely allowed enough space for his fingertips, and in some places he dangled by those fingertips, the only thing preventing him from dropping to his death.

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Alex Honnold -

Researchers are studying Honnold’s brain to try to understand how he achieved this. The mind is just as important as the body in a sport like this. A moment of doubt or hesitation can lead to certain death.

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Alain Robert -

Alex Honnold isn’t the only one crazy enough to attempt such stunts. French urban climber Alain Robert is famous for his daring ascents of the tallest buildings in the world. He is sometimes called the "French Spiderman."

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Cayan Tower -

In April 2015, he undertook one of his greatest challenges: the 1,000 ft (300 meter) Cayan Tower in Dubai (pictured, far left).

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Cayan Tower -

He successfully free soloed the entire building in 70 minutes by clinging onto the ridges and window ledges with his finger tips. Not to mention the building is twisted, so it wasn’t as simple as a straight climb.

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Petronas Towers -

He also climbed the famous Petronas Towers in Kuala Lumpur, Malaysia. The towers are 1, 500 ft (457 meters) tall.

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Busted -

He had attempted to climb them twice before, but on both occasions he was arrested when he reached the 60th floor (the towers have 88 storeys).

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Quite the 'record' -

In 2009, he finally managed to slip past the guards and make it to the top! At which time, however, he was promptly arrested...

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Eiger -

The Eiger in Switzerland is one of the most notoriously dangerous mountains in Europe. It was the subject of the 1975 Clint Eastwood film ‘The Eiger Sanction.'

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Dean Potter -

In 2008, two climbers made history on that mountain. The first was American climber Dean Potter. He climbed the infamous north face of the mountain during the summer when the rock face was dry.

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Dean Potter -

He used a different style of free solo called freeBASE. This means that he carried a parachute with him so he could use it if he fell, but had no other protective equipment apart from that. He is credited with inventing this style of climbing.

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Dean Potter -

Tragically, Dean Potter passed away in a base jumping accident in 2015. He and a partner jumped from a 7,500 ft (2,286 meters) cliff top, but their parachutes failed to deploy.

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Ueli Steck -

Swiss climber Ueli Steck climbed the icy north face of Eiger in the winter with record-breaking speed. The route usually takes three days, and he completed it in two hours and 47 minutes.

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Ueli Steck -

Ueli Steck also passed away 'on the job,' in 2017, while attempting a dangerous ice climb on Mount Everest alone.

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Brette Harrington -

In 2015, female climber Brette Harrington carried out the first free solo of the Chiaro di Luna route on the Fitz Roy Massif in Patagonia, Argentina.

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Brette Harrington -

The difficult 2,500 ft (300 meter) route took her just three hours. She had planned to attempt this record with her life partner Marc-André Leclerc, but sadly he died during a climb in Alaska. She managed to overcome the loss and make history on the mountain.

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Vitaliy Musiyenko -

On New Years Day 2016, the Widow’s Tears ice climb in Yosemite National Park was perfectly formed. It’s a rare occurrence and climber Vitaliy Musiyenko took the opportunity to try the daring ascent.

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Vitaliy Musiyenko -

The Ukrainian California-based climber made the 1,000 ft (300 meter) climb on the icy surface without any ropes or protective equipment. His only tools were his ice picks.

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Vitaliy Musiyenko -

He later stated that he would have gone using ropes if there had been a team available to assist him, but since there was no one around he took his chances and free soloed the climb alone. And he’s still alive!

Sources: (TED) (National Geographic) (Red Bull) (Climbing) (Mark Horrell)

See also: Breathtaking hikes to try all over the world

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