Legendary mountaineer Sir Ranulph Fiennes is a world class adventurer. His achievements so far include being the first man to visit both the north and south poles by surface means in his three year Transglobe Expedition in 1979, running a mind-boggling seven marathons in seven days on seven continents after undergoing a double heart bypass in 2003, and this year, at the age of 65, climbing to the summit of Mount Everest and he shows no signs of curbing his wanderlust any time soon.

According to the Guinness Book of World Records, Sir Ranulph is the ‘world’s greatest living adventurer’ but his latest book Mad Dogs and Englishmen: An Expedition Round My Family, takes a more personal path as audiences will discover when he puts in an appearance at Chorleywood LitFest next Wednesday.

I ask what made him decide to write the book about the Fiennes clan?

“I had a gap, or at least I thought I did – I didn’t realise Everest was going to get in the way. You see, it’s all very well thinking you’ve got forever, but then I had a heart attack and it was a good incentive to write a family history.”

Sir Ranulph, or Ran as he is known, has spent many years researching his family tree and has traced his family back for 41 generations, including 21 successive members who have lived at Broughton Castle in Oxfordshire for 600 unbroken years. At birth, Ran became the 3rd Baronet of Banbury and he is the third cousin of Hollywood stars Joseph and Ralph Fiennes, but now Ran can also add Charlemagne and the Boss of Boulogne, who very nearly persuaded William the Conqueror to retreat at Hastings, to his list of illustrious forebears.

Another old relation Godfrey, however, added a notorious branch to the family tree.

“He was not one I’d go for as being ideal. He was 24 and a lord of a huge estate in Kent with lots of deer but he thought it would be more fun to poach his neighbours’ deer and in the process he killed a gamekeeper and Henry VIII hanged him the next month. At Agincourt, on both sides the army generals were Fiennes cousins fighting each other and more were on opposite sides during the Wars of the Roses. Then there was a friend of the Prince Regent, who was a dandy and drank away all the family fortunes. He even sold the swans on the moat and rented out castle.”

The great and the good were joined by the bad and the downright ugly as Ran uncovered his ancestry, which quite often involved the intermarriage of cousins.

“There were so many characters, it’s unbelievable that they all exist in one family. There’s adultery and teenage elopement, cousins inter-married three times. Jane Austen was also a relation and her stories reflect that. These close cousins were very good for her stories, but she was kind enough to give them all aliases.”

Audiences can hear more of Ran’s adventures and exploits on Wednesday, November 18 at the Royal Masonic School, Rickmansworth, 7.30pm.

<>For more details on the line-up contact Chorleywood Bookshop: 01923 283566, www.cwlitfest.org