Which horse won the 1977 Triple Crown?

Seattle Slew was an American racehorse (Thoroughbred) who in 1977 became the 10th winner of the American Triple Crown—the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes—and the only horse to win the Triple Crown with an undefeated record.Seattle Slew was foaled on February 15, 1974, at the White Horse Acres breeding farm in Lexington, Kentucky. He had an impressive family tree: his sire, Bold Reasoning, was the grandson of Bold Ruler, the father of the great Secretariat. His dam was My Charmer, the offspring of Myrtle Charm, the champion two-year-old filly of 1948.

Seattle Slew began the Kentucky Derby by turning his head sideways and swerving to the right while the gate man tried to push him out of the stall. By the time he did come out, he was two or three lengths behind a wall of straining horses. By the time they reached the first quarter mile, Cruguet and Seattle Slew had left the herd behind and were challenging the leader, "For the Moment". The two horses ran head-to-head down the backstretch to the far turn, and Seattle Slew pulled ahead for good with a quarter mile to go.

A then-record crowd of 77,346 was on hand to watch the Preakness Stakes. Seattle Slew ran neck-and-neck with Cormorant for most of the race. Cruguet hit him once in the upper stretch to keep him focused and hand-rode him to the finish winning by 1 and a half lengths.

On Saturday June 11,1977, Seattle Slew won the Belmont Stakes and horse racing's Triple Crown.