The Queen’s funeral marks a major moment in history but her momentous 70-year reign was full of memorable milestones.

As the nation gives thanks to Her late Majesty for years of public service, mourners have lined the streets and gathered to watch the historic televised service.

The Queen passed away peacefully at Balmoral on Thursday, September 8 sparking a period of national mourning, but Monday’s state funeral will celebrate the life of the UK's longest-serving monarch.  

During her funeral and beyond, the Queen is remembered and celebrated for being a beloved ruler and for the more unique elements of her reign - including that she had two birthdays.

The Queen's life in pictures

Why did Queen Elizabeth II have two birthdays?

The Queen's two birthdays took place on April 21 (her real birth date) with the second being held on the second Saturday of June each year.

It is a tradition that can date back to the 1700s with a previous monarch having a summer celebration for the public outside of their actual birthday.

According to The Metro, the concept of having two birthdays started in 1748 by King George II who wanted to throw a public celebration to mark the occasion of his birthday.

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However, as he was born in November the likelihood of the weather holding out for such a celebration was slim.

Therefore he made two birthday dates, one for public celebration in the summer, and one for private in November.

This tradition has continued for over 250 years, with Queen Elizabeth now also celebrating two birthdays a year with one celebration in April and a public, official event in June.

The Queen's summer birthday took place on June 12 this year, shortly after her Platinum Jubilee celebrations. 

How was the Queen's birthday celebrated?

For the official event in June the Queen's birthday was marked by the Trooping of the Colour parade

The occasion is marked publicly by gun salutes in central London at midday: a 41 gun salute in Hyde Park, a 21 gun salute in Windsor Great Park, and a 62 gun salute at the Tower of London,’ states the official Royal Family website.

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Will King Charles III get two birthdays?

King Charles III was born on 14 November 1948 which makes currently him 73 years old.

Similar to King George II, who was also born in November, the new monarch would also celebrate a summer birthday under the current tradition.

The new King is expected to continue the 250-year-old custom as he approaches his 74th birthday.