Queen Elizabeth's 86th birthday was marked with gun salutes from across the country, led by a 62 gun salute at the Tower of London (by the Royal Gibraltar Regiment), a 41 gun honour at Hyde Park and a 21 gun salute at Windsor Great Park. Gun salutes were also held at York's Museum Gardens, the Portsmouth harbour and Edinburgh and Stirling castle.

There was a brief moment of chaos when horses scared by the gun salute from the King's Troop Royal Horse Artillery broke free at Hyde Park. The Queen, meanwhile, opted for a silent celebration at Windsor Castle, the official residence of London and the place she usually spends her weekends.

"The queen is spending the day privately," a Buckingham Palace spokesman told AFP.

The Queen christened as Elizabeth Alexandra Mary in the private chapel at Buckingham Palace is the oldest child of the Duke and Duchess of York. She married Lieutenant Philip Mountbatten, the great-great grandson of Queen Victoria in Westminster Abbey in 1947. The royal couple had four children - Prince Charles (b. 1948), Princess Anne (b. 1950), Prince Andrew (b. 1960) and Prince Edward (b. 1964). She assumed the throne after the death of her father, George VI, at an early age of 27, on 2 June, 1953.

However, the Queen will celebrate her "official" birthday in June; the exact date, additionally, varies from country to country within the Commonwealth. The Queen and other members of the royal family attend the Trooping the Colour military parade in central London during the celebration of her "official" birthday.

Incidentally, this year also marks the 60th anniversary of her Accession to the throne - her Diamond Jubilee - and will be celebrated splendidly. One of the planned events is the largest ever flotilla in 350 years, down the River Thames.

Her Majesty is the second-longest reigning British monarch in history, second only to Queen Victoria, who ruled for 63 years.

A glimpse through the life of the Queen and celebration of gun salutes...

Gunners from the King's Troop Royal Horse Artillery arrive to fire a forty-one gun salute in Hyde Park, central London April 21, 2012. Saturday marked Britain's Queen Elizabeth's 86th birthday.Reuters
Gunners from The King's Troop Royal Horse Artillery prepare to fire a round during a forty-one gun salute in Hyde Park, central London April 21, 2012. Saturday marked Britain's Queen Elizabeth's 86th birthday.Reuters
Gunners from the King's Troop Royal Horse Artillery fire a forty-one gun salute in Hyde Park, central London April 21, 2012. Saturday marked Britain's Queen Elizabeth's 86th birthdayReuters
People watch as gunners from The King's Troop Royal Horse Artillery fire a forty-one gun salute in Hyde Park, central London April 21, 2012. Saturday marked Britain's Queen Elizabeth's 86th birthday.Reuters