Queen Elizabeth II survived a potential attack as she rode a horse down the Mall in London in 1981.
As the late monarch rode her horse Burmese at her annual birthday parade, Trooping the Colour, six shots - later discovered to be blanks - were fired at close range.
Marcus Sarjeant, 17, from Folkestone, was sentenced to five years in prison. He was a former air training cadet who had joined the Royal Marines and quit within months.
The Queen was praised for her composure during the incident, and is remembered for how she was able to control her horse.
Sign up to our newsletters.