5 Most Popular Extreme Sports in the US

2. Rock Climbing

Insider Monkey Score: 7

Even before climbing star Alex Honnold’s stunning ‘free solo’ ascent of Yosemite’s El Capitan in 2017, rock climbing was gaining a foothold. Now, with its debut at the 2020 Tokyo Olympics, the once niche sport is reaching new heights.

Yet the popularity of rock climbing and its sister sport, bouldering (where climbers scramble up large rocks without the use of ropes or harnesses), is raising questions about the damaging environmental effects of climbing chalk – a ubiquitous and essential climbing tool.