Queen Elizabeth II marked her official birthday on Saturday with the annual Trooping the Colour parade, a traditional display of British pageantry at its very best.

The parade has marked the official birthday of the reigning British monarch for more than 260 years, and this year featured more than 1,400 soldiers, nearly 300 horses and 400 musicians in a ceremony on Horse Guards Parade in Westminster.

The display closed with a fly-past by Britain's Royal Air Force.

Royals taking part included Prince Charles, Prince William and his wife Kate, and Prince Harry and his wife Meghan who appeared in her first public outing since giving birth to their son, Archie, to watch the birthday fly-past of military aircraft.

Baby Archie did not appear, but another young royal almost stole the queen's limelight when he made his debut on Buckingham Palace's balcony. One-year-old Prince Louis, the youngest child of the Duke and Duchess of Cambridge, waved frantically at the first of the helicopters in the show.

The queen marks her birthday twice a year an official ceremony is always held in June, in hopes of holding the parade in good weather. Her actual birthday, on April 21, is usually celebrated with close family only.

Thousands of spectators lined the parade ground and gathered in nearby St James's park to watch the spectacle in sparkling sunshine. They then walked down the road leading to Buckingham Palace, gathering at the gates to honor the monarch ahead of the fly-past, the punctuation mark of the annual event.

It's been a big week for the monarch. Demonstrating the close link between the monarchy and the armed forces, she was the centre of ceremonies marking the 75th anniversary of the D-Day landings, the invasion of France that marked the beginning of the end of the Nazis.

But if the 93-year-old sovereign was tired, it didn't show. She waved and smiled as she emerged on the balcony and the crowd roared.

The ceremony originated from traditional preparations for battle. The colors or flags were “trooped,” or carried down the lines of soldiers, so they could be seen and recognised in battle. The regimental flag being paraded this year is from the 1st Battalion Grenadier Guards.