King Charles and Queen Camilla had a regal day in some historic headpieces.

The royal couple attended the State Opening of Parliament in London on Wednesday, May 13, marking the formal start of the parliamentary year and setting the government’s agenda for the session.

King Charles, 77, and Queen Camilla, 78, traveled from Buckingham Palace to the Houses of Parliament in a horse-drawn carriage through the streets of London in the Irish State Coach (which has been used in royal events, including bringing Queen Elizabeth to her 1947 wedding to Prince Philip). They then entered the House of Lords chamber in a grand procession.

King Charles wore the Imperial State Crown during the ceremony. He first wore the historic headpiece at his coronation in May 2023. Although he was officially crowned with the St. Edward’s Crown, which is only used to crown a new king or queen during the coronation ceremony, he swapped it for the Imperial State Crown toward the end of the service.

The crown, which dates back to the 1937 coronation of King George VI, is made of gold and set with 2,868 diamonds, 17 sapphires, 11 emeralds, 269 pearls and four rubies.

King Charles has previously worn the Imperial State Crown for other State Openings of Parliament since the start of his reign. It was displayed on Queen Elizabeth’s coffin during her funeral in September 2022.

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Camilla first wore the headpiece, also called the George IV State Diadem, at the first State Opening of Parliament of her husband’s reign in November 2023. The diadem was made for the 1820 coronation of King George IV — and it’s what the monarch wore on his way to Westminster Abbey for his crowning ceremony.

Since King George IV, the Diamond Diadem has been worn by every British queen, whether they reigned or were consorts: Queen Adelaide, Queen Victoria, Queen Alexandra, Queen Mary, Queen Elizabeth (the Queen Mother) and Queen Elizabeth.

The diadem moment comes weeks after Queen Camilla went without a tiara at the state dinner hosted by President Donald Trump at the White House during the royals’ visit to the United States.

During the State Opening of Parliament, King Charles delivered the King’s Speech, which is written by the government and contains an outline of its policies and proposed legislation for the new parliamentary session.

Throughout her historic 70-year reign, Queen Elizabeth would sport the Imperial State Crown during the State Opening of Parliament annually. However, as she got older, she would opt for a lighter diadem or one of her signature wide-brimmed hats for the event steeped in tradition. Since the crown weighs over 2 lbs, it’s understandable why the late sovereign made the switch.

Queen Elizabeth spoke about the challenge of reading the speech at the State Opening of Parliament while trying to balance the heavy headpiece in the documentary The Coronation: “You can’t look down to read the speech, you have to take the speech up. Because if you did, your neck would break — it would fall off. So there are some disadvantages to crowns, but otherwise, they’re quite important things.”

Although King Charles has attended the State Opening of Parliament as monarch in recent years, he first attended the event in 1970 and attended the event several times before the start of his reign, accompanying his mother.

He memorably stepped in for Queen Elizabeth at the event in May 2022. Buckingham Palace announced that the Queen, who died in September 2022 at age 96, would miss the event due to “episodic mobility problems.” For the first time, Charles represented his mother and read the Queen’s Speech.

While King Charles and Queen Camilla were busy in London, Kate Middleton arrived in Italy for a two-day visit tied to her work supporting early childhood development. It marks the first work trip abroad for the Princess of Wales since 2023, as she spent much of 2024 out of the public eye amid her cancer diagnosis and treatment. Kate announced she was in remission in early 2025 but has spoken out about the “really difficult” period that comes after treatment is over as well.

“This is an important step in the Princess’ recovery journey. She takes great joy from this work,” an aide said ahead of the tour. “I think it is only right that her first international trip since her illness is one that is focused on an issue she is committed to championing for decades to come.”