Double Olympic rowing gold medallist James Cracknell is set to make his way from the United Kingdom to Africa in an amazing challenge for Sport Relief.
He will row the English Channel and cycle around 1,400 miles through France and Spain before arriving in Gibraltar.
Then, with Sport Relief Super Swimmer and Little Britain star David Walliams, he will swim the treacherous Strait of Gibraltar all the way to Morocco.
Cracknell, 35, will begin his journey this week, if weather conditions allow.
The rower needs to time his challenge precisely to ensure favourable conditions for the final swim, and he aims to finish in just seven days.
Throughout the challenge Cracknell will only be stopping to rest for four hours in every 24 hours.
The ultimate aim is to raise as much money as possible for Sport Relief and you can show your support for him by making a donation to Sport Relief.
Show your support for James Cracknell's amazing challenge
Cracknell has been getting some useful swimming tips from Walliams, who raised more than £1m for Sport Relief by swimming across the English Channel in 2006 .
They both battled freezing weather conditions for their first open-water training session at Dorney Lake in Windsor at the end of January when they were shown no mercy by trainer Professor Greg Whyte.
James said: "We hyperventilated when we first got in the water because it was so cold and after that your whole body just goes numb.
"I'm going to need all the help I can get by the end of this challenge and David is a real pro so having him there on the day will be a massive boost."
'There's going to be sharks'
The 36-year-old Little Britain star, who plans to swim the 12-mile stretch of the Strait of Gibraltar, said that although the distance is shorter than the English Channel there would be other problems to face.
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"It's colder and there's sharks in it and also the sea's a lot rougher, so I think it's going to be a very challenging swim," he said.
This year the big Sport Relief buzz word is 'challenge' and the idea is to do something sporty to raise cash.
The ultimate way to get involved is to take part in one of the Sainsbury's Sport Relief Miles which are happening across the UK on 16 March.
This year, participants can set their own challenge by having the choice of completing one, three or six miles.
There will be well over 200 Sport Relief Miles around the UK, so there is bound to be one close to you. All you have to do now is sign up and start getting yourself sponsored.
Sign up for your nearest Sport Relief Mile
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