Former Royal Marine Mark was just under four months into a tour of duty in Afghanistan when he stepped on a landmine, losing both legs above the knee and his right arm in the explosion.
But refusing to let his life-changing injuries defeat him, he threw himself into fundraising to help other injured veterans.
Since starting with shaving his beard, Mark, from Plymouth, has taken on progressively harder challenges, including a 1km swim across Plymouth Sound and a 99.9-mile bike ride, and raised more than £519,000 for charity.
Unaware that he was up for an award, Mark, 38, was joined on stage by two dames – Paralympic athlete Dame Sarah Storey and actress Dame Joan Collins.
Speaking afterwards, he said: “I didn’t have a clue. It was a shock and overwhelming but, ultimately, I’m just proud.
“It has been a crazy year and I have an amazing team behind me. This is the cherry on the cake.”
And Mark, who was standing in between Dames Sarah and Joan, joked: “And to be presented by two dames, two legends, I feel like the filling in a very beautiful sandwich.”
An emotional Dame Joan added: “A dame sandwich! You are fantastic, inspiring and spectacular, and I am so impressed. When I saw your video it made me cry. You are so brave, it’s making me cry now.”
Dame Sarah said: “It’s just truly inspiring. What Mark has achieved is just remarkable.
“Most of us can’t imagine what that will be like and we feel very fortunate for people like Mark who are there for us and are looking after us – he really is the pride of Britain.”