Veteran explorer Sir Ranulph Fiennes will take on "the toughest footrace on Earth" in April - the Marathon des Sables in Morocco - in a bid to raise millions for charity and become the oldest Briton ever to complete the race.
Sir Ranulph, who turns 71 in March, must run 156 miles across the Sahara in 50C heat to complete the six-day ultramarathon.
He hopes to raise £2.5 million for Marie Curie, which provides care and support to terminally ill people and their families across the UK.