LONDON, ENGLAND - SEPTEMBER 09:  The Royal Barge Gloriana leads a procession along the River Thames near Tower Bridge and HMS Belfast to pay tribute to Queen Elizabeth II becoming Britain's longest reigning monarch on September 9, 2015 in London, England. The Queen will have served for 63 years and seven months - 23,226 days - by around 5.30pm today surpassing her great-grandmother Queen Victoria to become Britain's longest ever reigning monarch.  (Photo by Carl Court/Getty Images)