Queen Elizabeth II appeared at a traditional military parade in London on Thursday, opening celebrations to mark 70 years since her coronation.
The parade, known as Trooping the Color, kicked off a series of special events running through the weekend to celebrate the platinum jubilee.
Thousands of royal fans of all ages and nationalities lined the procession route hoping for a chance to see the monarch.
Lynette Bailey, 64, from Essex in southeast England, was in the crowd with her children and grandchildren.
"It's a once-in-a-lifetime event. I don't think my grandchildren will see another platinum jubilee," she said.
One couple from London in their 60s, who also attended the queen's diamond jubilee in 2012, said, "We think she has been an amazing queen for seventy years...we want to celebrate everything she's done for us."
The queen ascended the throne in February 1952 following the death of her father, King George VI, and was crowned on June 2 the following year.
The 96-year-old is the first British monarch to reach a platinum jubilee. In 2016 she became the world's longest-serving living monarch, following the death of Thailand's King Bhumibol Adulyadej.
Festivities will include nationwide street parties and a star-studded concert featuring acts such as Queen and Elton John. National celebrations will conclude Sunday with a pageant recreating major moments from the queen's reign.
The milestone follows a difficult period for the royal family, which saw the death of the queen's husband, Prince Philip, in April 2021 and the withdrawal from royal life of her grandson, Prince Harry, and his wife Meghan Markle the previous year.
Some uncertainties had remained surrounding appearances by the monarch during the celebrations. The queen has had to miss number of recent engagements due to mobility issues, with Prince Charles, heir to the British throne, standing in.