The trio were full of mirth as they enjoyed the Braemar Gathering in Aberdeenshire, central Scotland, which is roughly 15 miles from Balmoral.
Always an entertaining highlight in the British royal calendar, the Highland Games featured traditional events such as the tossing of the caber, tug of war and a children's sack race.
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The Queen sported a cream hat and coat, embellished with beads, and kept out the cold with a warm tartan blanket as she watched proceedings from the royal pavilion.
Charles, who is known as the Duke of Rothesay in Scotland, wore a traditional kilt and sporran and a moss green jacket.
The 93-year-old Duke of Edinburgh matched his son's highland dress, opting for a brown waistcoat and blazer.
As the games drew to a close, the Queen was tasked with presenting the awards. The 88-year-old monarch received a bunch of heather from one participant before presenting the cups and shields.
The Duchess of Cornwall did not join her husband Charles at the games as she is currently on holiday in Ibiza with her children.
Also notably absent was Prime Minister David Cameron, who has previously attended the event with his wife Samantha, as it is thought he felt it inappropriate given Scotland's forthcoming vote on independence.