Today is a momentous day in British royal history. Her Majesty the Queen has been on the throne for a total of 63 years, seven months and two days, making her the longest reigning British monarch in history. Queen Victoria used to hold the title but is now being surpassed by Queen Elizabeth II, who at nearly 90 is also the oldest ruler to still be on the throne.

1. Her Majesty needs official permission to enter the City of London

Even though she is sovereign of the United Kingdom, Her Majesty the Queen is not allowed to enter the City of London without the permission of its Lord Mayor.

2. The Queen is the only person who is allowed to drive without a licence.

Driving licences are issued in the Queen’s name, so it would be silly for her to give herself a licence. Don't let this make you think she can’t drive – during the Second World War she operated a first aid truck for the Women’s Auxillary Territorial Service.

3. She celebrates two birthdays a year

Although the Queen's actual day of birth is the 21st of April, her "official" birthday is celebrated is celebrated on a Saturday in June, usually the second one

4. She's never short on cash because she has her very own ATM inside Buckingham Palace

5. The Queen does not have to pay tax, but does so voluntarily

In 1992, the Queen volunteered to pay income tax and capital gains tax. Since 1993 her personal income has been taxable as for any other taxpayer.

6. Elizabeth II has sent over 175,000 telegrams wishing happy 100th birthday

During her reign she has wished 175,000 centenarians in the UK and the Commonwealth a happy birthday. Will she make it to her 100th birthday? The question on everyone's lips.

7. The Queen has created a new breed of dog known as the "Dorgi"

This is a cross between a corgi and a dachshund. One of the Queen's beloved corgis mated with Princess Margaret's dachshund named Pipkin, spawning the world's first "dorgi". Since then there  have been 11 dorgis - Tinker, Pickles, Chipper, Piper, Harris, Brandy, Berry, Cider, Candy and Vulcan.