American climber claims to be first to solo the most brutal line on Denali, the tallest mountain in the US, but labels the Alaska Range a "hellscape" after punishing 53-day trip

Denali mountain.

American alpinist Balin Miller is claiming to be the first person to solo the famous Slovak Direct climb on Denali mountain in the Alaska Range.

It's the first known solo ascent of the route, which leads to the right of the Cassin Ridge, and has only been completed 20 times in total since the 1980s.