Her Majesty marked her 90th birthday by meeting some of the thousands of well-wishers with the Duke of Edinburgh by her side on Thursday 21st April.
Achieving a milestone as Britain's oldest and longest-reigning monarch, she usually celebrates this day in private and has a more public celebration in June.
On her walkabout in Windsor she received armfuls of cards, bouquets of flowers and even a cake as she acknowledged the greetings of the crowds for this historic milestone for the monarch.
By her side was 94-year-old Prince Philip, her husband of 69 years, with whom she has four children, eight grandchildren and five great-grandchildren.
But this is only one of the two birthday celebration for Her Majesty. For four nights next month there will be a musical pageant in Windsor, involving 900 horses and some 1,500 actors, dancers and musicians, celebrating the queen's nine decades.
On June 11th comes the monarch's "official" birthday, traditionally marked by the Trooping the Colour military parade.
This year there will also be a service at St. Paul's Cathedral and a huge street party in the Mall outside Buckingham Palace for members of charities the queen supports. The government has even given pubs permission to stay open later on June 10th and 11th, until 1 a.m. instead of the standard 11 p.m.
MUST-KNOW FACTS ABOUT HM QUEEN ELIZABETH II
- The Queen has two birthdays – the 21st April marks the date she was born. She also gets another knees up on 11th June - that’s known as her official birthday.
- She became Queen at the age of 25.
- HM Queen Elizabeth II is Britain’s longest reigning monarch and has seen off 12 prime ministers during her reign.
- Rumour has it if she wants to leave a dinner in five minutes, she puts her bag on the table to indicate to her staff that she’s ready to leave. She moves it from arm to arm to tell aides she is tired of talking to someone.
- She has owned more than 30 corgis during her reign, her first one, Susan, was an 18th birthday present.
- Prince Philip’s pet names for The Queen are said to include ‘sausage’ and ‘cabbage’.
- She made her first public speech when she was 14, when children were being evacuated for safety reasons.
- She loves a crime thriller. Some of her favourite authors are PD James, Agatha Christie and Dick Francis.
- She has her own train but usually travels round the UK by helicopter or RAF aircraft.
- She’s head of state of 15 Commonwealth countries: Australia, New Zealand, Canada, Jamaica, Antigua and Barbuda, Belize, Papua New Guinea, St Christopher and Nevis, St Vincent and the Grenadines, Tuvalu, Barbados, Grenada, Solomon Islands, St Lucia and The Bahamas.
- Most Wednesdays, at 6.30pm, she has a meeting with the Prime Minister. Nobody except the two of them knows what is said during this time – these meetings are confidential.
- She’s the patron of more than 600 charities.