When a 25-year-old Elizabeth assumed the throne from her father, King George VI, on February 6, 1952, no one could've guessed that she'd one day become the longest reigning monarch.
In 2017, she celebrated a Sapphire Jubilee, which marked her 65th year on the throne. Her Majesty also had a number of other special occasions to commemorate last year, including her 70th wedding anniversary with Prince Philip, and her grandson, Prince Harry's engagement to Meghan Markle.
This year will mark the monarch's 92nd birthday, and although there's still a lot of time until her birthday rolls around, it's never too early to take a look back at some of the most memorable moments from her life:
One-year-old Elizabeth makes one of her first appearances on the Buckingham Palace Balcony.
The future queen is pictured arriving at Olympia for the annual Royal Tournament.
Elizabeth poses beside her younger sister, Margaret, who was born three years prior.
The then-princess stands beside her mother on the Buckingham Palace balcony after the coronation of her father as King George VI.
The future queen was just 14-years-old when she delivered one of her first public addresses.
Elizabeth became a Girl Guide in 1937, and during the World War, she was tasked with boosting public morale.
Elizabeth joined the Auxiliary Territorial Service (ATS) in 1945, and trained for weeks to polish her basic motor mechanic skills and learn how to drive a truck.