Harry, the fifth in line to the British throne, set up the multi-sport Invictus Games three years ago for wounded military personal from allied nations.
The 2017 edition will take place in Toronto, Canada from Sept. 23-30 with more than 550 injured and wounded servicemen and women from 17 allied nations expected to take part in 12 adaptive sports.
Harry met with British competitors in athletics and indoor rowing hoping to win one of the 90 places on offer.
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"I don't know how you found yourself so brave to come and join. I say brave enough because I know some of you coming to an event like this and trying to get yourself on the plane to Invictus Games can be quite a tough challenge," he told the potential recruits.
"I would love to see all of you there but the reality is that we only have 90 places. But what I do hope is that your journey up to this point has been a recovery no matter what."
The Invictus Game were held in London in 2014 and Orlando in 2016.
(Writing by Patrick Johnston; editing by Mark Heinrich)
