Published: 09:36, 05 July 2019
| Updated: 15:19, 05 July 2019
A man will cycle, swim and run for 289 miles to raise £1 million for charity.
Chris Leek's effort will include swimming the Channel from Dover.
He will try to break a world record by completing the triathlon in less than 74 hours.
Chris Leek, 32, from Orpington south London, is taking on the Enduroman Arch 2 Arch from London's Marble Arch to the Arc de Triomphe in Paris.
The challenge, starting on Friday, August 2, with an 87-mile run from London to Dover.
He then takes on a 21-miles swim from Shakespeare Beach to Calais and follows this with a 181-mile bike ride to the French capital.
He is to become the fifth ever person to take on the challenge without a wetsuit for the swim.
The current world record for a non-wetsuit solo effort is 73 hours and 39 minutes.
Mr Leek is doing this for three charities, Parkinson's UK, Lewy Body Society and Orpington's Saxon Day Centre.
The Lewy Body Society is a charity trying to fund research into Lewy body dementia, the second most common progressive dementia after Alzheimer's disease.
Mr Leek is doing this for his father Dennis who has both LBD and Parkinson's disease a progressive neurological condition caused by a loss of nerve cells.
Christopher Leek, a beer sales manager for the Budweiser Brewing Group, has been training for eight months.
The exact dates of the triathlon are expected to be confirmed later.
Mr Leek says: “I’ve done a few physical challenges in my time, but this will be the biggest by a long way.
" My dad is such a huge motivation, and thinking about raising this money for him, and people in a similar condition, will keep me going when things get tough.
" If I can not only break the world record, but also raise that £1 million, this will be a dream come true.”
If you want to back Mr Leek visit the website virginmoneygiving.com/ChristopherLeek
Read more: All the latest news from Dover