Prince Philip has attended his final solo royal engagement.

On Wednesday, the husband of Queen Elizabeth II officially retired after announcing plans to take a step back from his royal duties in May. In his career as a member of the royal family, Prince Philip has attended 22,219 solo engagements, made 637 overseas visits, given 5,496 speeches and authored 14 books.

As captain general of the Royal Marines, Prince Philip attended a parade to pay tribute to the end of the 1664 Global Challenge at Buckingham Palace.

"The Duke met representatives from the @royalmarines runners' contingent, including two Royal Marines who have completed the entire 1,664 miles," the royal family shared on its official Instagram alongside a slideshow of highlights from the day. "His Royal Highness also spoke to veterans and cadets before returning to the dais to receive the 1664 Global Challenge baton. The Royal Marines are the amphibious troops of the Royal Navy, acknowledged as one of the world's elite commando forces."

The duke received three cheers from marines and was handed the 1664 Challenge Baton during the parade. He was appointed captain general of the Royal Marines in 1953.

The royal family broadcast the duke's last day of work on its official Facebook page.

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