Walking With The Wounded: Iceland training for South Pole race
Imagine trying walk to the South Pole if you are totally blind or missing a limb.
That is exactly what three teams of injured servicemen and women from around the world are training for, an international race across Antarctica in aid of Prince Harry's charity Walking With The Wounded.
The teams, from Britain, the US and the Commonwealth, have been in Iceland getting their first taste of what to expect ahead of the race later this year.
The BBC's Security Correspondent Frank Gardner went along to join them.