Injured soldiers treated at a rehabilitation centre in Surrey will drive a horsedrawn ambulance hundreds of miles for charity.
The team, which was treated at Headley Court, in Epsom, will travel non-stop from Land's End to John O'Groats.
They will drive a replica World War I ambulance during the challenge and hope to raise £1m.
Organisers say the money raised from the event will be donated to charities which help injured service personnel.
The journey will begin in June and is expected to last nine days.
Organiser Jacks El Tawil is an NHS paramedic who helped mentor members of the forces in frontline first aid.
She said: "There will be eight war wounded who have been training for at least six months to ride and drive.
"The wagon will roll 24/7 and we're hoping to cover 120 miles a day using 22 horses.
"There are 2.6 soldiers per day having life changing injuries [in Afghanistan] at the moment.
"I felt guilty that I wasn't aware of that and thought we ought to try and raise a bit of money to help these guys along a bit."
Matt Wilson, who lost his left leg and severely damaged his left arm when he stepped on a pressure-pad of a concealed roadside bomb in Sangin, Afghanistan, in 2009, will be one of the drivers.
He said: "I'm here to tell another tale and that's thanks to the brilliant help through Headley Court and the main charities we will be supporting on our event."
The money raised will be donated to Help for Heroes, ABF The Soldiers' Charity, the British Limbless Ex-Servicemen Association and Combat Stress.