Will Bosi: Brit sending the hardest boulders in the world

In the world of pro climbers, few have made the jump from competition to the great outdoors quite like Will Bosi. In only 2 years, he has quickly ascended to the ranks of the world’s top climbers crushing some of the hardest boulders in the world thus becoming the first and only to have climbed four 9A/V17, his latest being Spots of Time.

So it’s fair to say we’d all love to know how Will reached this pinnacle, and what makes him one of the best boulderers in the world today.

From the gym to the great outdoors: Bosi’s climbing evolution

Image from Instagram @will_bosi

Will Bosi is originally from Edinburgh and started climbing like most of us – at the local climbing gym. Hooked, he got into competition climbing and fast-forwarded to being part of the GB team.

However, despite having experienced successful comp results including his best performance in the IFSC adult circuit in 2019 (4th place), and his attempt to secure a spot in the 2020 Tokyo Olympics, Bosi decided to fully transition to outdoor bouldering.

And ever since Bosi’s rise was kind of extraordinary. After being the first British male competitor to final in a World Cup in decades, he became the second Brit to climb 9b, and the youngest to have climbed 9a with his repeat of Rainshadow at Malham Cove.

And recently he was crowned as the first and only climber to have four of the hardest boulders on the planet: Alphane, Return of the Sleepwalker, Burden of Dreams, and Spots of Time.

The rise of Will Bosi in the climbing world

Undoubtedly his comp achievements have placed him amongst the elite climbers. However, his decision to focus on outdoor climbing has truly created the space for him to reveal his full potential in ways no one really anticipated – maybe not even him.

To Bosi, not qualifying for the Olympics in 2020 – something which for some competitors would be devastating, turned out to be a turning point in his career and the very moment when he started to shine.

While many climbers struggle between competition and outdoor climbing because they both require different sets of skills and training, for Bosi the switch seemed almost like a revelation.

Many young climbers dream of qualifying for the Olympics and therefore chase competition glory.

What does Will Bosi do? The exact opposite: quits competing and finds his calling on the boulders.

As a result, from being yet another competitor who trains for the Olympics, he becomes the strongest boulder on the planet and sends the hardest 4 boulders in the world!

Bosi’s breakthrough: sending the hardest boulders in the world

Rest assured, there are a handful of 9a/V17 boulder climbers in the world. Names such as Elias Iagnemma, Nalle Hukkataival, Simon Lorenzi, Shawn Raboutou, Jakob Schubert, Aidan Roberts, Camille Coudert, Nico Pelorson, Daniel Woods, and Charles Albert have managed this amazing performance.

Let’s take a closer look at some of the hardest boulder problems in the world and how Will Bosi stands out.

Alphane (9A/V17)

Alphane (9A/V17) is located in Chironico, Switzerland, and is the playground of the world’s best climbers.

This boulder with nine high-end crushing moves was discovered by Dave Graham and first climbed by the American climber Shawn Raboutou in April 2022.

Alphane is one of the hardest boulder problems on the planet that made Bosi a 9a/V17 climber in October 2022.

Burden of Dreams (9A/V17)

Burden of Dreams (9A/V17) is a 4m red granite 8-move boulder problem located in Finland. Nalle Hukkataival did the FA in 2016.

Bosi made the first repetition and climbed it in only 52 seconds.

Notoriously difficult, requiring mastery of micro-crimps and minuscule footholds, Bosi spent over 4 months projecting it (both on a replica and the boulder itself in Finland) and declared that this was the hardest boulder he’d ever climbed.

Return of the Sleepwalker (9A/V17)

Return of the Sleepwalker (9A/V17) is a 17-move problem in Red Rocks, USA. In February 2024, Bosi became the second climber to send Return of the Sleepwalker.

Daniel Woods needed 52 sessions to make the first ascent, while Bosi achieved it in just 12, showcasing not only his immense talent but also his remarkable ability to quickly learn and adapt to the line’s challenges.

Spots of Time

Spots of Time is I quote “one of the world’s most beautiful lines”, a 9A boulder located in Lake District, UK.

This Britain’s Hardest Boulder was FA by Aidan Roberts and was repeated by Will Bosi in just 24 sessions (out of which 10 were on a replica).

So I guess now it’s double send and historical ascent for the UK.

How does Will Bosi train to send the hardest boulders in the world

Image from Instagram @will_bosi

What does it take to send the world’s hardest boulder problems? We assume it comes down to 3 main ingredients: time, hard work, and strategy.

And a matter of personal skill. Or should I call it a personal spark?

Regardless, all that skill would not mean anything without precision, finger strength, and an impeccable sense of body positioning.

So how do you get all of that?

Skill is unique: As much as Will Bosi’s training regimen and its effectiveness are.

He is famous for his short warm-up sessions and flash sends when other normal climbers are still getting their bodies ready for the session.

But not Will. He trains 3 times a week, between 4-5 hours a day at the climbing gym.

Let’s dive deeper into the subject and see how the former member of the GB team trains.

The one and only: the indoor not-climbing warm-up

Bosi’s warm-ups typically start with dynamic stretches and easy traverses along the bouldering wall. This helps him activate his muscles and get his fingers acquainted with the holds before moving on to harder problems.

Fingerboard and campus board training

A reference in Bosi’s training is fingerboard and campus board exercises to help him develop the explosive power and grip strength required for the hardest boulder problems.

He often starts with easy hangs to loosen up his tendons and then moves on to 100 campus moves before the actual climbing session.

From long dynamic reaches, matching, and twisting on the campus board, these moves are mandatory as a preparation for more intense sessions that push his finger strength to their limits.

His campus board routine includes dynamic movements like 1-3-5, 5-7-9, and more complex combinations.

Climbing-specific warm-ups

But wait, there’s more! Will doesn’t neglect the importance of body coordination and footwork. Therefore, the following part of his warm-up and training routine is activating the legs for more intense climbing.

He starts by climbing easier vertical or slab problems to engage his legs and core before gradually moving on to more overhung terrain.

As the session progresses, he increases the difficulty, warming up with four or five problems just below his project level.

Game on: The intention of the training for the bouldering session

A typical Bosi session involves attempting 10 hard boulders just below his project level. He’ll climb four warm-up boulders graded around 8a, followed by six to eight 8b boulders.

These problems are done with 3 to 5 attempts each, giving him the chance to work on the intricacies of each climb without burning out too early.

And, very importantly, skin economy.

What’s Will’s secret exercise to progressing in climbing?

Believe it or not, the strongest boulderers at the moment did not always have such strong fingers. Ever since he started to work with Lattice Training, the young Brit gradually improved his finger strength.

One of his favourite exercises is the single fingerboard hang, which he has progressed to over time, starting with two-arm hangs and using pulley assistance. But that’s not all.

Bosi also sees a great deal in campusing and he often does 12 to 14 campus power endurance moves. Just like Megos’s in here.

Would you survive Will Bosi’s training session? Go on and try.

However, be mindful and remember to always adjust training according to your level. The only way to go to the top is to start building progressively from the beginning.

How to look after your skin when sending hard boulders

Is your skin too dry, or too wet? Do you just get splits fast? From CRIMP oil for fast recovery and calming of the inflammation in your fingers to Rhino skincare product line, at Boulderflash you can find everything you need to send hard.

Also, by reading our guide on climber hands and skincare you’ll have all the tips you need to help your skin recover faster.

Is Will Bosi the best boulderer on the planet?

If until recently he was at a tie with Simon Lorenz and Aidan Roberts, thanks to his repetition of Spots of Time, Will Bosi undoubtedly becomes the best boulderer in the world.

He is now not only the first and only climber to have climbed four 9a/V17 boulders but he has also done it at a speed that no other boulderer in history can match.

What’s his secret? I guess it is as simple as that: discover something you are passionate about and dedicate your life to it.

Bosi is living proof that when things don’t work out the way you want them to, it’s because they are due to work even better.

We are aware hard climbing takes time and is not a walk in the park.

However, witnessing Will crushing it, our bet on is now on him to climb the first V18.

What do you think?

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