Walking with the Wounded's Christmas campaign 'Walking Home For Christmas' is officially underway.
It aims to raise money for the charity, which helps vulnerable and homeless veterans get back on their feet.
Participating are Walking with the Wounded CEO Ed Parker, and RAF veteran Duncan Slater.
They'll be doing a 119-mile walk from London to Norfolk with no money, food, or accommodation along the way.
The idea is to raise awareness for homeless and vulnerable veterans. As Ed Parker puts it:
"90%+ leave the military and successfully transition into civilian life. But there is... a 10% number of people who do find it challenging, who find it difficult to get a job. Often they can't find a house, and so those are the people that we're working with".
Duncan Slater, meanwhile, had both legs amputated after his vehicle hit a roadside bomb in Afghanistan, but says he's got very comfortable new legs. He's committed to helping other veterans in trouble:
"It's horrendous that anyone has to live on the streets, and live rough. It's awful. And a big part of that is guys that have served".
Duncan Slater has said that people can honk their horns if they see them along the way, and any spare change would be very much appreciated.