Since 1952, there have been seven Popes, 14 US Presidents and 15 British Prime Ministers. But there's only been one British monarch.

Queen Elizabeth II reigned for more than 70 years — longer than any British monarch in history.

She was 25 years old when she ascended to the throne.

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Elizabeth was born April 21, 1926, in London. She is held here by her mother, also named Elizabeth. Her father would later become King George VI.

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Queen Elizabeth II with her oldest son, Prince Charles, in 1969. Charles, immediately became King of the United Kingdom upon the death of his mother.

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Elizabeth listens to her great-grandson, Prince George, outside a church where George's sister, Charlotte, was being christened in July 2015.

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The Queen rides a horse in Windsor, England, in May 2020. It was her first public appearance since the first coronavirus lockdown began in the United Kingdom.

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The Queen drives her Range Rover as she attends the Royal Windsor Horse Show in Windsor, England, in July 2021.

Check out more photos from extraordinary life of Britain’s longest-serving sovereign in our gallery here.