A replica of Magna Carta is to be carried down the Thames as part of events to mark its 800th anniversary.
The Royal Barge Gloriana will lead 200 boats from Hurley in Berkshire to Runnymede in Surrey over two days.
Magna Carta was granted by King John on 15 June 1215, establishing that the king was subject to the law rather than being above it.
Twenty three local people have been chosen as” charter bearers”to relay the document reports BBC.
The pageant, which starts at 09:00 BST, has been organised by Thames Alive, with support from Royal Borough of Windsor and Maidenhead, Runnymede borough and Spelthorne borough councils.
The event will culminate with the unveiling of a 4m (13ft) bronze statue of the Queen at Runnymede Pleasure Grounds.
Principles set out in Magna Carta charted the right to a fair trial and limits on taxation without representation.
It also inspired a number of other documents, including the US Constitution and the Universal Declaration of Human Rights.