Louisville, Kentucky became a center of horse racing attention on May 17, 1875, when Churchill Downs opened its doors for the first time. It was also on this day Kentucky Derby made its debut.

The first Kentucky Derby was run at 1.5 miles, the same distance as the Grand Prix de Paris. In 1896, the distance was changed to 1.25 miles, and is currently raced at this distance. The first race was held in front of a crowd of around 10,000 people. Fifteen horses competed in the inaugural race, and the first winner was horse Aristides and his rider, Oliver Lewis.

Vagrant won the second Derby in 1876. Secretariat won in 1973 setting the track record. Man of War never won the Kentucky Derby.

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