Jumping off a platform 1,300 metres up a mountain cliff is not everybody's idea of fun... but dozens of competitors flock to the biannual World Base Race in Norway and Switzerland to do just that.
The jumpers use their specially-designed wing suits to 'fly' before releasing parachutes to glide safely to the bottom; the winner is the fastest glider to an agreed point at the bottom of the cliff.
The competition was founded by inventor Paul Fortun, 43, back in 2008, and he takes a hands-on approach to organising, telling Caters: "I handpicked the best cliffs I can find, and then jump off them to test them!
"It sounds very dangerous but we make sure we are as safe as we can be by minimising risks and setting targets.
"Everyone who turns up to do a jump has to have done more than 80 free jumps from a cliff or aeroplane before, to make sure they are capable."
He added: "I'm terrified every time I jump, everyone is. I think if you're not scared of something like this then why bother.
"It's all about the taste of fear and lack of control, I love it."
Fancy testing your nerve? Try one of these extreme holiday activities:
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