File photo dated 07/09/55 of Queen Elizabeth II at Doncaster racecourse to see the St. Leger, an avid racing fan, she began riding lessons at the age of three and is known for her knowledge of thoroughbreds and breeding. PRESS ASSOCIATION Photo. Issue date: Sunday September 6, 2015. Queen Elizabeth II has been monarch for more than 63 years and is set to become Britain's longest reigning monarch on September 9. See PA story ROYAL Reign Photos. Photo credit should read: PA Wire
