The Triple Crown of Thoroughbred Racing, often shortened to Triple Crown, is a series of horse races for three-year-old Thoroughbreds. Winning all three of these Thoroughbred horse races is considered the greatest accomplishment in Thoroughbred racing. The term originated in mid-19th-century England and nations where Thoroughbred racing is popular each have their own Triple Crown series.

Sir Barton (April 26, 1916 – October 30, 1937) was a champion American Thoroughbred racehorse who is the first winner of the American Triple Crown.