In June this year, US rock climber Alex Honnold became the first person to free climb the iconic, close to 914-metre vertical granite wall called El Capitan in Yosemite National Park, California. Free climbing means that no ropes or safety gear are used, making the ascent of the notoriously hard rock face what may be the greatest feat of pure rock climbing ever. Honnold has spoken about the perceived riskiness of his sport several times. Here are some of his comments on risk.