London:
Queen Elizabeth II marks the 60th anniversary of her coronation on Sunday, starting a series of events including a return to Westminster Abbey where she was crowned as a 27-year-old.
Elizabeth, now 87, took the throne on February 6, 1952 upon the death of her father king George VI, but to allow for a period of national mourning, she was only crowned 16 months later.
A service celebrating the anniversary is being held on Tuesday in the abbey in London where, on a rainy summer's day in 1953, she was anointed and the imperial state crown was placed on her head.
The coronation anniversary is being staged with far less fanfare than the diamond jubilee celebrations last year.
Royal thoughts are now turning to the birth expected in July of Prince William and Catherine's baby, whom -- following a change in the rules of succession -- will be third in line to the throne regardless of gender.
Barring unforeseen circumstances, William and Catherine's child will eventually be crowned in Westminster Abbey.
The coronation celebrations include exhibitions of memorabilia, gun salutes and a series of garden parties.
Royal biographer William Shawcross said that by living out her coronation oaths of duty and service, the queen had been a focal point during the momentous social upheaval of her reign.
"Britain was then another world. It has changed beyond recognition since 1953. Only the queen has remained our constant," he wrote in the The Daily Telegraph newspaper.
"That unity around the crown has, amazingly, remained -- and it is centred on the young woman who has grown older with us."
That Britain's system of government has perhaps worked never better than under Queen Elizabeth "is at least in part because she is utterly true to everything she experienced at her coronation", he wrote.
The young sovereign made her solemn oaths at Westminster Abbey on June 2, 1953. It was the first time a coronation had been televised and more than 20 million in Britain watched events live while another 11 million listened to radio coverage of the ceremony.
Despite the rain, the streets were packed with wellwishers wanting to see the procession, with the monarch travelling in the Gold State Coach. The event was seen as heralding a new Elizabethan age following the hardships of World War II, which had ended just eight years earlier.
Though the anniversary falls on Sunday, the sovereign will be marking the day in low-key fashion and is expected to stay at Windsor Castle to the west of London and attend the regular church service there.
"The queen will be spending Sunday privately," a Buckingham Palace spokeswoman told AFP.
On Tuesday, Queen Elizabeth and her 91-year-old husband Prince Philip will be joined by senior royals and around 2,000 guests for the celebration service at Westminster Abbey.
The imposing gothic church has witnessed 38 coronations dating back to that of William the Conqueror in 1066, while 18 British monarchs are buried inside.
Justin Welby, the Archbishop of Canterbury, is to give the address, while British Prime Minister David Cameron and the Commonwealth Secretary-General Kamalesh Sharma will give readings.
A specially-written poem by the Poet Laureate Carol Ann Duffy will also be read out.
Those invited include participants from the 1953 coronation, the high commissioners from her other realms such as Australia, Canada, New Zealand and Jamaica, and guests from every county in Britain.
Events marking the anniversary are already under way.
The abbey is hosting a public exhibition of photographs from the coronation day, while the Royal Mail has released a set of stamps featuring six portraits of the queen, spanning her reign, commissioning a painting of the monarch for the first time in its history.
The queen was presented with a replica of her coronation bouquet on Thursday by the Worshipful Company of Gardeners, crafted by the grand-daughter of the original florist.
On Monday, a 41-gun royal salute will be fired in London's Green Park, followed by a 62-round salvo from the Tower of London.
At Buckingham Palace, an exhibition of outfits, artworks and objects from the coronation day, including the white satin dress the queen wore, will go on show from July 27.
And a four-day Coronation Festival is being held in palace gardens from July 11 to July 14, showcasing the brands which are the official suppliers of goods and services to the senior royals.