Entry has opened for the Queen’s Diamond Jubilee Thames river pageant, which is expected to be seven and a half miles long.

60 years after her coronation the Queen will travel in a Royal Barge at the head of the 1000-boat flotilla on Sunday June 3 2012.

Letters have been sent to the High Commissioners of every Commonwealth country and the Lord Lieutenants of every British county inviting each to send a vessel for the flotilla.

The pageant’s website – www.thamesdiamondjubileepageant.org – is now open for boats to register and will close on October 31.

All vessels must be able to maintain a steady speed of four knots and pass under Westminster Bridge, which has a clearance height of 5.4m.

Everyone selected will have received an invitation to take part by the end of the year. Unsuccessful applicants will also be informed by then.

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