To mark the occasion, a new photograph of the Queen standing between two white ponies has been released.
The photograph has the Queen holding two of her own fell ponies by the reins, with Bybeck Nightingale on the right and Bybeck Katie on the left.
The new portrait taken last month in the grounds of Windsor Castle, has been released by The Royal Windsor Horse Show to mark the occasion.
This will be the Monarchs second birthday without the Duke of Edinburgh who died on April 9, last year - only two months before his hundredth birthday.
The Queen is expected to stay at Wood Farm cottage, a property loved by her late husband, the Duke of Edinburgh.
In the Queen's yearly message, she renewed the promise she made on her 21st birthday, declaring that "my whole life whether it be long or short shall be devoted to your service and the service of our great imperial family to which we all belong."
So, after a year of health scares, and mourning her husband, acknowledging that “none of us will live forever,” it seems reaching the remarkable age of 96 is worth celebrating.
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