On Garter Day, Prince William donned the traditional outfit, which consisted of a velvet robe and feathered hat, just for the special celebration.
He attended the parade along with many others to commemorate the oldest and most senior order of knighthood in the United Kingdom.
The 35-year-old prince, who stunned everyone with his get-up, joined the Order of the Garter parade and service at St. George’s Chapel in Windsor, where Prince Harry and Meghan Markle’s wedding took place in May.
Prince William was joined by his father, Prince Charles – a Knight Companion in the Order, Queen Elizabeth – head of the Order of the Garter, along with other senior royals.
Last year, the annually-held event was canceled after the date of the State Opening of Parliament was unexpectedly moved after a surprise general election.
The celebration pays tribute to the new inductees to the Order of the Garter, which is the "oldest and most senior Order of Chivalry in Britain," as stated by the Royal Family’s official website.
Other members of the Royal Family like Camilla, the Duchess of Cornwall, and Sophie, the Countess of Wessex, were also present to watch the parade.
Prince Harry and Meghan Markle were noticeably not around to enjoy the procession, as well as Kate Middleton who is still on maternity leave since giving birth to Prince Louis in April 2018.
Prince Phillip was also missing in action since he already retired from his official royal duties in 2017.
In 2008, two years before he was engaged to Middleton, Prince William was officially inducted to the order.
The Garter Day starts of a week-long celebration at Windsor. The Queen headed the Royal Ascot racing on June 19th which will continue on through the rest of the week.
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