Elizabeth Marks wants to donate the medal to the hospital that saved her life.
The smiling fan named Ruth chatted with the British royal Thursday at the Paralympic-style games for wounded military veterans.
Sgt Elizabeth Marks won gold at the Invictus Games - but then she handed her medal back to Prince Harry.
"I feel invisible a lot of the time," Katie Kuiper tells PEOPLE
"We're the lucky ones to have witnessed it together," the royal says on the last day of Invictus
Sergeant Elizabeth Marks donated her Invictus gold medal to the institution as a thank you for saving her life in 2014.
Sergeant Elizabeth Marks also told the Good Morning Britain how "overwhelmed" she is by support from across the world
Prince Harry has lauded injured veterans during the closing ceremony of the Invictus Games.
Sergeant Elizabeth Marks, 25, asked Prince Harry to take one of her four medals back to England with him to give to the doctors and nurses at Papworth Hospital in Cambridgeshire.