With a reign spanning almost 70 years, Queen Elizabeth II has seen plenty of changes during her time on the British throne.
While she may be the world's longest-reigning monarch, the US President doesn't spend anywhere quite as long in the Oval Office as the royal has in Buckingham Palace.
During Queen Elizabeth II's sovereignty, 14 men have held the title of President of the United States. The royal has met 12 presidents since taking the throne, with that number set to rise to 13 later this month.
The queen is scheduled to meet US President Joe Biden, who took office in January, when he visits the UK for the G7 summit on Sunday, June 13.
Scroll through the gallery above to see photos of Queen Elizabeth II with 12 US presidents.
The monarch, 95, will also meet Jill Biden, the first lady, at Windsor Castle, marking her first meeting in person with a foreign head of state since the pandemic hit.
The only US president the queen did not meet was Lyndon B Johnson, who served between 1963 and 1969.
She was unable to meet Johnson, who took over from the assassinated John F Kennedy, at the late politician's US funeral, as she was pregnant with Prince Edward.
During his presidency, Johnson and the queen are believed to have communicated many times, according to the LBJ Presidential Library, but did not meet in person.
"Queen Elizabeth never sent an invitation to President Johnson to visit Great Britain. And, President Johnson never sent an invitation to the Queen to visit the United States," archivists from the library state.
However, Queen Elizabeth II's sister, Princess Margaret, attended a White House dinner with Johnson during her US tour in 1965.