London (CNN) Meghan, Duchess of Sussex, was making her first appearance at a public engagement Saturday since the birth of her son, Archie Harrison Mountbatten-Windsor, at the traditional Trooping the Colour, a celebration of the Queen's official birthday.

She emerged from Buckingham Palace in a horse-drawn carriage, sitting next to her husband Prince Harry, Catherine, the Duchess of Cambridge, and Camilla, the Duchess of Cornwall.

Wearing a blue hat, the Duchess of Sussex waved to thousands of people who had gathered along the Mall in London to watch the spectacle, in which more than 200 horses, 400 musicians and 1,400 officers are taking part.

Meghan made her first appearance at a public engagement Saturday.

The monarch is technically the head of Britain's armed forces, and would traditionally lead an army into war. The parade, which gives the Queen a chance to review her army, moves from Buckingham Palace down the Mall to Horse Guard's Parade, with members of the royal family traveling on horseback or carriage.

Meghan and Prince Harry make their way in a horse-drawn carriage to Horseguard's Parade ahead of Trooping the Colour.

When the Queen was younger, she would ride side-saddle on horseback to greet the public. But in recent years, she travels by horse and open carriage.

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