After sitting on the throne for 66 years, you'd expect Queen Elizabeth II to have witnessed a number of poignant events - from royal births and weddings to political upheaval and a new age in technology.
But there have been some things more sinister than others, and it doesn't seem like the Queen will ever forget them.
Andrew Parker-Bowles, who was the former husband of Camilla, Duchess of Cornwall and was previously in charge of the royal household cavalry, has revealed the Queen's "most ghastly" day of all.
In an interview with The Express, Parker Bowles told of the event: July 20 1982, the day of the Irish Republican Army's attack on London.
"It was a nice, sunny day and suddenly one heard this explosion one heard all the time in Northern Ireland."
"One of the barriers opened and someone said, 'They've blown up the Guard'. So we ran down to where the smoke was rising."
This attack occurred during the changing of guard ceremony, resulting in the death of four soldiers and seven horses.
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Only a few hours later, a second blast went off under the bandstand at Regent's Park where the British Army band played. It killed seven people and wounded others.
Parker Bowles told the publication: "[Queen Elizabeth] said to me it was 'the most ghastly day of my life'."
The life of the world's longest reigning sovereign is certainly filled with historical moments that won't be forgotten in a long time, and the hit TV show The Crown proves it.
The Netflix series chronicles the reign of Queen Elizabeth II, detailing the events of both her personal life while it intertwines with real world events at the time.
The Queen herself was said to be a fan of the show, however last week it was revealed she was unhappy with the portrayal of Prince Philip in one particular season two scene.
A senior courtier revealed to The Express that the Queen was upset about an episode where Charles is depicted as the victim of bullying during his school days at Gordonstoun.
In one scene, Philip displays no sympathy for his troubled son, which apparently wasn't the case in real life, according to Queen Elizabeth.
"Philip has no sympathy for a plainly upset Charles while he is flying him home from Scotland. That simply did not happen," the courtier said.
"I can convey that [Queen Elizabeth] was upset by the way Prince Philip is depicted as being a father insensitive to his son's wellbeing."
- PuzzlesThe Australian Women's Weekly July Issue Online Entry
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