On Saturday, an American rock climber by the name of Alex Honnold became the first person to free-solo the El Capitan granite rock formation in Yosemite National Park.

If you're wondering what 'free-soloing' means, it basically means he scaled the vertical wall without any ropes or safety equipment of any kind - with just a bag of chalk to keep his hands dry. Basically, he's a real-life Spiderman.

El Capitan (below) is 3000 feet tall and is a challenge for even experienced climbers with full safety equipment - which makes the 31-year-old Honnold's achievement is all the more remarkable. It's been described as 'the moon landing' of free-soloing.

Honnold's climb took just under four hours and was filmed for National Geographic, with the full feature film coming later in the year. He had trained for the challenge for over a year, and first attempted the climb last November - but put the brakes on it after an hour because conditions 'didn't feel right'.

For now, this taster of both the height of the wall, as well as the mental and physical skill needed for such a feat is serious sweaty-palms territory: