By Victoria King
The inaugural Band of Brothers bike ride last year raised £1.4m
On Sunday, 240 cyclists set out to pedal 350 miles across France. The journey is a challenge for all those taking part, but especially for several of the riders who were wounded while serving in the Armed Forces in Iraq and Afghanistan.
The servicemen - and the rest of their two-wheeled colleagues - are trying to raise a large sum of money for forces' charity Help for Heroes.
Their trip from Portsmouth will take them all the way to Paris and will hopefully beat last year's total of £1.4m.
Co-founder of Help the Heroes Bryn Parry told the BBC News website: "It's so inspiring, cycling along beside these guys.
"They have shown unbelievable courage, but they don't expect anything for it. They don't want sympathy, they just want opportunities. They just want to be normal."
Help for Heroes was created in 2007 and has so far raised more than £20m, some £8m of which has gone to build a new swimming pool and gym complex at Headley Court forces' rehabilitation centre in Surrey.
Bryn is hoping funds raised by the Band of Brothers bike ride will make a significant dent in the next £20m - needed to build seven Hero Recovery Centres at garrison towns across the UK.
These "half-way houses", as he calls them, will have space for 20 servicemen or women at a time and the first will open in Edinburgh in August.
"We want to give injured personnel some breathing space," he said. "When they've been to Headley Court, but aren't ready to go back to their battalion or civilian life.
"It'll be a really nice, warm environment. Each person will have their own room, their own bathroom. There'll be carers on hand in case they need anything.
"Then every day each resident will have an individually tailored programme, depending on their personal ambition or injury.
"They might want to carry on in the military, say as a clerk, so they'll go back into the garrison for re-skilling. Others, who want to move on, will be given the chance to do work experience or take part in off-site training.
"The idea is that it will be a place of transit, where they can be helped back to life, whether it be civilian or military."
Emma and Bryn Parry founded Help for Heroes in 2007
Reservist Trooper Adam Cocks is one of those cycling the route. The 26-year-old, from Parsons Green in south-west London, is a member of the Territorial Army.
He will take part in the ride using a hand bike - pedalling with his arms not his legs - because of injuries he suffered in Afghanistan.
Adam said: "I've been training with the hand bike for about eight weeks, but the hills are still going to be an absolute killer.
"I'm determined to get up them unaided though."
While on operations in Afghanistan in 2007, Adam's vehicle struck a mine and his leg was severely damaged. Since then he has endured eight operations and is still not able to use it properly.
"When I came back from Afghanistan I knew I wanted to do something for Help the Heroes," he said. "It's such a great charity and produces real tangible results.
"I think the recovery centres are vital. They'll be a stepping stone and hopefully help people cope with the mental injuries as well as the physical ones."
Just a couple of weeks before the 65th anniversary of D-Day, the race has added poignancy because it takes in some key World War II battle sites.
Leaving Portsmouth, the riders were waved off by actor Ross Kemp, who has recently become a patron of Help for Heroes and has spent extended periods with British troops in Afghanistan.
Once on French soil, they will wind their way to Paris via a number of battlefield sites, paying tribute to the different Allied nations as they go.
Remembering the Americans, they will visit Omaha beach, scene of the D-Day landings.
On British Day, they will enjoy a spectacular fly-past before heading to Pegasus Bridge, where the first house to be liberated from the Germans in June 1944 still stands.
Adam, top right, organised a charity rugby match for Help for Heroes
There the cyclists will be accompanied across the bridge by pipers and a bugler sounding The Advance.
Days four and five of the trip will remember the Canadian, Polish and French efforts and will involve former members of the French resistance.
Bryn says he wants people to be proud of both the more distant and more recent contributions to Britain's Armed Forces.
"I'm trying to make people see that servicemen and women are the same people today as they were in 1944," he said.
"All those qualities - like determination, humour, valour, bravery - that we think of as belonging to a lost generation are still alive and well.
"One guy said to me on last year's ride, 'Look, I'm not disabled, I just haven't got an arm.' It's that sort of attitude."