A river pageant is underway in London to mark Queen Elizabeth's Diamond Jubilee.
Up to a million people have lined the banks of the Thames, despite heavy rain, to watch the Queen travel down the river in her royal barge accompanied by a flotilla of 1,000 boats, the BBC reported.
The river pageant will be the most spectacular nautical parade in London for 350 years, the BBC said. It is being held at the start of celebrations to mark 60 years of Queen Elizabeth II's reign,
Jubilee-themed concerts and street parties are being held around Britain today in celebration.
Queen Victoria is the only other British sovereign to have celebrated a Diamond Jubilee.
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Boats will travel a seven-mile route on the Thames, starting at Hammersmith and ending at Tower Bridge. Some 20,000 people are aboard the vessels.
Queen Elizabeth, 86, is expected to spend two hours traveling down the river in her lavish barge, accompanied by her husband Prince Philip and various other members of the royal family.
The flotilla is divided into 10 separate squadrons, many of them with bands playing as they move downstream, The New York Times said.
Jubilee celebrations will continue until June 5, with Monday and Tuesday declared as public holidays.
CNN said an afternoon garden party at Buckingham Palace on Monday will be followed by a televised pop concert outside the palace grounds.
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