The world’s greatest living explorer, Sir Ranulph Fiennes, is getting ready to take on ‘the toughest footrace on earth’, the Marathon des Sables, in a bid to become the oldest Briton to ever complete the race. Sir Ranulph says he's not done with fundraising yet despite raising over 16.8 million so far.

Sir Ranulph, who lives in Cheshire, turns 71 this March. He will be embarking on this monumental feat in April in a bid to raise £2.5million for UK charity Marie Curie. Sir Ranulph says he's undergoing strict fitness training to ensure he's up for the challenge.

The money raised will help the charity to provide more free care and support to people living with any terminal illness, and their families, across the UK. Sir Fiennes says his aim is to raise 20 million in his lifetime and he's become a bit obsessed about achieving his goal.