- Prince William surprised runners at a Sandringham half marathon with George and Charlotte.
- They spoke to 1,300 runners before they undertook half marathons, 5k runs, or a community mile.
- The event took place at the Sandringham Estate, where the Queen spends Christmas each year.
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Prince William surprised runners at the Sandringham half marathon with an appearance and speech, accompanied by his children Prince George and Princess Charlotte.
The event took place on Sunday as many celebrated Father's Day, and saw the Duke of Cambridge and his eldest two children address 1,300 runners before the race began.
Runners at the Sandringham Run could choose from 13.1 miles (half marathon), a 5k run, or a community mile around the royal estate and surrounding trails in Norfolk, where the Queen spends Christmas.
Aaron Murrell, the Race Director of Run Sandringham, told Insider: "We were really happy that HRH The Duke of Cambridge joined us as our Official Race Starter – along with his two children George and Charlotte."
"The runners really enjoyed seeing them there as our special guests, and there was a fantastic atmosphere within the event village as they joined us on stage to start the Half Marathon event," he added.
Murrell told Insider that fundraising proceeds from the event went toward supporting three local charities: East Anglian Air Ambulance, Break, and East Anglian Children's Hospices.
The Duke and Duchess of Cambridge also used Father's Day as an opportunity to honor the fathers in their family with a video post on Instagram.
The post included an image of Kate Middleton walking down the aisle with her father Michael Middleton at her 2011 wedding, one of William and Prince Harry as children with their father Prince Charles at the Balmoral estate in 1993, and a photograph of the late Prince Philip with the Queen and the seven grandchildren they had at the time it was taken in 2018.
The final photo the couple included was a previously unseen image of William with all three of his children, likely taken during Trooping the Colour in 2019, the last time the full event was held as a result of the pandemic.