Kate, 37, came ready to win in her sporty sailing attire. She wore black spandex shorts, gray trainers, a blue sports cap and a gray raincoat.
William, 37, sported a navy blue hat, a waterproof black coat, black shorts and gray sneakers.
The sailing race is held every year to raise money for eight different charities the royal couple supports.
The Duke and Duchess of Cambridge were competing against each other in the boat race and each foundation was represented by a different sail in the race.
William and Kate are patrons of charities such as Child Bereavement UK, London’s Air Ambulance Charity 30th Anniversary Campaign, Tusk, Action on Addiction, and The Royal Foundation.
Celebrities like Bear Grylls, John Bishop and Helen Glover also competed.
The King's Cup Sailing Regatta was originally scheduled for Friday, August 9. However, due to the stormy skies and inclement weather, the event was held one day prior.
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