American Triple Tiara of Thoroughbred Racing

The Triple Tiara of Thoroughbred Racing, formerly known as the Filly Triple Crown, is a set of three horse races in the United States which is open to three-year-old fillies. Presently the only official Triple Tiara is the three race series in New York; they are: The Acorn Stakes, run at Belmont Park at a distance of 1 mile, The Coaching Club American Oaks, run at Saratoga Race Course at a distance of 1⅛ miles and The Alabama Stakes, also run at Saratoga at a distance of 1¼ miles.

There have been attempts to develop a "Filly Triple Crown" or a Triple Tiara for fillies only, but no set series of three races consistently remained in the public eye. At least four different configurations of races have been designated as such. Two fillies won the series of the Kentucky Oaks, the Pimlico Oaks (now the Black-Eyed Susan Stakes), and the Coaching Club American Oaks, in 1949 and 1952, but the racing press did not designate either accomplishment as a "triple crown." The New York Racing Association designated three of its races as a filly triple crown of sorts, but the races so designated changed over the years. Eight fillies won variations of the NYRA Triple Tiara between 1968 and 1993.

The original Triple Tiara consisted of three races at Belmont Park: the 1 mile Acorn Stakes, the 1⅛ mile Mother Goose Stakes and the Coaching Club American Oaks, which varied in distance between 1¼ and 1½ miles.

Eight horses have won the series under this system:

*A* = Denotes that the horse also won the Alabama Stakes in the same year, which has been part of the Triple Tiara series since 2010, and was also part of that series from 2003 through 2006.

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