The royal duo and the Canadian Prime Minister gathered with Prince Charles at the Vimy Memorial Park in northern France for the historic event's 100th anniversary, where the Prince of Wales as well as Trudeau delivered a speech honoring the fallen service members.
Both William and Harry laid a pair of boots and poppies of remembrance at the Canadian National Vimy Memorial site during the ceremony, which was attended by an estimated 25,000.
Now only a few days into the start of April, the famous Brits have already been hard at work on their various service projects.
Last week, Prince Harry delivered the keynote address at a reception for Landmine Free World 2025 in which he asked for help in maintaining a promise his mother, Princess Diana, made to two victims of landmines that the explosive device would cease to exist by 2025. He also attended Invictus Games trials for the Unite Kingdom teams.
Later this evening, the trio will reconvene for a reception celebrating Canadian athletes that have competed in the royal redhead's annual Invictus Games and other military personnel.