'I absolutely love it' – Adam Ondra attempts possibly the world's hardest boulder problem

Adam Ondra
Adam Ondra is arguably the world's best climber (Image credit: Getty Images)

Adam Ondra has been attempting a boulder problem that, if climbed, could be the world's first V18. The project, named Imothep Assis, is located in France's forest of Fontainebleau, one of the bouldering world's most historic regions.

This problem has been a longtime project of Camille Coudert, French boulderer and local Bleausard (a climbing term for a Fontainebleau climber). One of the elites, he repeated Fontainebleau's V17 Soudain Seul in 2022, first climbed by Simon Lorenzi in 2021 and one of the hardest boulder problems in the world.

Coudert has been projecting the boulder for several years – see below for his successful send of Imothep du Sol. Having grappled with the Imothep Assis variant, Ondra reckons it is "possibly a 9A+ (V18) from the sit start". No one has ever climbed a consensus V18 boulder problem, so if Imothep Assis was to be conquered, and the grade agreed upon, it would be a seismic moment in bouldering history.

Ondra, one of the world's greatest climbers, had previously claimed the fourth ascent of Soudain Seul in February 2025. His more recent Fontainebleau exploits saw him flash other highly technical problems, including Imothep du Sol (V13/14), Ubik Assis (V13) and Ligne de bête (V14).

To 'flash' a climb is to send it on the first attempt using prior knowledge, either gleaned from watching others on the route or reading up on it. This is as opposed to an 'onsight' whereby the climber sends the route first time with no prior knowledge.

In his Boulder Tour de Fontainebleau film (which you can watch below), Ondra had this to say of Imothep Assis: "I absolutely love it. I think it's the most motivating boulder I've ever seen."

Boulder Tour de Fontainebleau | Adam Ondra - YouTube Boulder Tour de Fontainebleau | Adam Ondra - YouTube
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Alex Foxfield

Alex is a freelance adventure writer and mountain leader with an insatiable passion for the mountains. A Cumbrian born and bred, his native English Lake District has a special place in his heart, though he is at least equally happy in North Wales, the Scottish Highlands or the European Alps. Through his hiking, mountaineering, climbing and trail running adventures, Alex aims to inspire others to get outdoors. He's the former President of the London Mountaineering Club, is training to become a winter mountain leader, looking to finally finish bagging all the Wainwright fells of the Lake District and is always keen to head to the 4,000-meter peaks of the Alps. www.alexfoxfield.com