Britain's Queen Elizabeth today led a flotilla of 1,000 boats in a gilded royal barge down the River Thames in London today in a spectacular highlight of four days of nationwide celebrations to mark her 60th year on the throne.
Hundreds of thousands of people armed with Union Jack flags and wearing red, white and blue clothes and hats, poured into the capital from early morning, braving wind and rain to line the 11km route of one of the largest flotillas ever seen on the river.
Up and down the country, millions more were attending diamond jubilee street parties over the long holiday weekend in honour of the 86-year-old queen, the only British monarch after Queen Victoria to have sat on the throne for 60 years.
"With the economy the way it is, this is why we have to have this celebration. It gives people a lift," said Kevin Rogers (54), who travelled across southern England with his wife and son to bag a viewing spot at London's Albert Bridge.
Organisers say today's pageant was the largest of its kind in 350 years since a similar spectacle was held for King Charles II and his consort
Catherine of Braganza in 1662.A floating belfry with a set of eight church bells specially cast for the celebrations was at the head, with bells from riverbank churches pealing out as it passed by.
The queen was on board The Spirit of Chartwell barge with her 90-year-old husband Prince Philip and other members of the royal family including heir-to-the-throne Prince Charles, his eldest son Prince William and wife Kate.
Other vessels included Motor Torpedo Boat 102 on which Allied Forces commander General Dwight Eisenhower (later US president) and British prime minister Winston Churchill inspected warships before the 1944 D-Day invasion of Nazi-occupied France.
The flotilla travelled under 14 bridges and past 14 miles of bunting. Another of the boats, Amazon, also featured in diamond jubilee celebrations for Queen Victoria, Elizabeth's great-great-grandmother, in 1897 when Britain's empire spanned much of the globe.
Although the queen is still head of state in 16 countries from Australia and Canada to tiny Tuvalu in the Pacific Ocean, Britain is now a shadow of the world power which once ruled over more than a third of the planet.
Historians and commentators say the jubilee and the pomp and pageantry synonymous with British royal occasions gives the country a sense of national pride at a time when the economy is in recession and people face deep austerity measures.
The government also hopes it will kick-off a summer of revelry capped off by the Olympic Games in London which will raise the public's spirits and their own poll ratings.
"One of the great things that a monarch brings and, particularly a royal family and her majesty the queen personally brings, is this sense of national unity and stability - someone who the whole country can identify with," British prime minister David Cameron said on BBC TV in a broadcast today.
The celebrations come as polls show the vast majority of Britons support the monarchy, which has overcome a slump in the 1990s following marital infidelities and the death of the hugely popular Princess Diana in a 1997 Paris car crash.
Last year's wedding of Prince William to Kate Middleton was proof of such enduring appeal with the ceremonial extravaganza attracting a global audience of up to two billion people.
However, not everyone in London will be cheering. The small yet vocal republican movement plans a protest during the flotilla, saying the jubilee was "a celebration of inherited power and privilege, and those celebrations have no place in a modern democracy".
But even they acknowledge there is almost no chance that the queen will be ousted and take solace in indications many Britons are simply indifferent - two million people are leaving the country to take advantage of the extended public holiday.
"Some people will hate this day, some think it is a waste of taxpayer money, but I think the queen has been a great leader and the royal family brings a lot of tourism to England," said Rachel Harrison (41), her face painted with a Union Jack.
Celebrations will continue on Monday with a pop concert outside Elizabeth's London residence Buckingham Palace, where Paul McCartney and Stevie Wonder will be among the acts. Madness are set to take to the roof of the famous landmark to belt out hit song Our House.
The long weekend concludes with a service of thanksgiving at St. Paul's Cathedral on Tuesday followed by a carriage procession along the broad Mall leading to Buckingham Palace where the queen will wave to the crowds from the balcony.
For the police, today's flotilla presented a new security challenge.
"We've had officers searching under the water, on the water, in the air and on the land," London police's Deputy Assistant Commissioner Stephen Kavanagh said.
Reuters