The recommended time for a charity bike ride from the tip Cornwall to end of Scotland is 14 days - but a Northampton duo are going to do it in seven.
Michael Hollowell and postman Gary McDaniels are gearing up to conquer the 1,000 miles from Land's End to John O'Groats in just a week.
It means the two Northampton men - who are both less than a year away from 50 - will have to pedal 140 miles a day.
But they are both confident they will make it to the finish line in support of two charities close to their hearts.
Michael, who works for Northamptonshire Police, said: "I'm looking forward to it - but I must admit I'm a bit scared. It's going to be tough going.
"I just wanted to achieve something in time for my 50th birthday and raise a bit of money for a good cause."
Michael, from Kingsthorpe, is taking on the challenge for Autism East Midlands, a charity which has supported his family ever since his daughter Grace was diagnosed with autism when she was six.
Meanwhile Gary, from Brixworth, will pedal for the Roy Castle Lung Cancer Foundation in support of his mum, who was diagnosed with the disease in 2017 and is battling it today.
Gary said: "Although we are both regular cyclists, this challenge is in another league.
"Sometimes it feels like on of those ideas that sounded good at the time. But it's going to be a challenge and I know when we're out there all we will think about is making it to the next stop and raising a bit of money."
They start their journey on June 16 from Land's End at 7am in the morning, and they are booked in for hotels for every night along the way.
"Looking forward to a shower and a sleep will be a small comfort each day at least," said Michael.
Gary and Michael have set a fundraising target of £2,000 to split between their charities. For more information, visit the pair's SponsorMe page here.
Meanwhile, a branch of Rutland Cycles at Pitsford Resevoir have stepped forward to help the pair with saddle bags for their bikes to thelp the duo cart their kit across the country.