Ultracyclist Lee Fancourt has begun his attempt to break the world record for riding from Lands End to John O'Groats and back again.
The Gloucester native set off from the Cornish landmark at 5am on Monday morning, with the challenge to get to the tip of Scotland and back in under five days, 21 hours and eight minutes.
With many riders having tried and failed to break the record in recent years, Fancourt is under no illusions as to the huge task he faces this week.
"The task ahead is massive, lets hope the weather gods are on my side, at present the weather looks good for the first leg up to John O Groats," he said on his Facebook account.
"I've had a good sleep & feel ready for this mammoth of a challenge. I may have had longer challenges in the past but this one will be the toughest."
Fancourt plans to ride for 24 hours straight on the first day, according to the Gloucester Citizen, to get a chunk of the challenge behind him.
The current record, set by former University of Bath student Ben Rockett, has stood for five years since being set in August 2010.
Rockett's support crew put together this great video showing just how challenging the ride is.
Fancourt comes into the challenge on the back of cycling through seven European countries in the space of 24 hours, finishing last Monday.
His trip took him through Czech Republic, Slovakia, Austria, Hungary, Slovenia, Croatia and Bosnia and saw him cover 323 miles in the day.
You can track Fancourt's progress on his website - as of 2.30pm on Monday he was just short of Taunton, having covered 151 miles.
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