The Somerset explorer has been speaking of his experience as the NHS turns 75 today. 

'A thousand thanks to the NHS' - Sir Ranulph Fiennes recalls heart attack

He is perhaps the world's greatest adventurer and is now embarking on a new challenge

'I want to make my wife and daughter proud' - Sir Ranulph Fiennes on his career

The 72-year-old had to be helicoptered from the mountain, when he was just a few hours from the summit on Monday.

Sir Ranulph Fiennes admits he "should be ten years younger" as he attempts to climb one of the world's most dangerous mountains.

The explorer from Exmoor is taking on Aconcagua in Argentina - the tallest mountain in the continent and the second tallest in the world.

Sir Ranulph Fiennes has announced his latest challenge - to be the first to cross both polar ice caps & climb each continent's highest peak.

Sir Ranulph Fiennes has called on PM Theresa May not to repeal the ban on fox hunting, saying the Conservative Party should "move on"

The famed explorer is taking on arguably his most grueling challenge yet - a 56-mile run in the 50-degree heat of the Moroccan desert.

71-year-old explorer is aiming to become the oldest Briton to complete the Marathon des Sables to raise money for charity.

The British explorer will travel across Antarctica during the southern winter, where temperatures can plummet to -90C.