The Kentucky Derby is the first leg of the American Triple Crown series for 3-year-old Thoroughbreds. Held each year at Churchill Downs in Louisville, Ky., on the first Saturday in May, the track has presented the race continuously since 1875. The Derby is run at the distance of 1 1/4 miles and is arguably the most famous horse race in the world.

Horses compete in the Kentucky Derby after qualifying through a series of preparatory races known as the Road to the Kentucky Derby. These stakes races are held at racetracks across the country and award Derby qualifying points to the top four finishers. The Derby starters are comprised of the horses with the most qualifying points, with two of the 20 spots reserved for the top qualifiers from the European and Japanese Road to the Derby qualifying events.  

The Kentucky Derby has many traditions, including drinking mint juleps, wearing festive hats, and singing "My Old Kentucky Home" as the horses enter the track. Its sister race, the Kentucky Oaks, exclusively for 3-year-old fillies, takes place the day before the Kentucky Derby, on the first Friday in May. Both Oaks Day and Derby Day are treated as local holidays in Louisville.  

The horse who wins the Kentucky Derby receives a blanket of red roses, the official flower of the Kentucky Derby. The race is commonly referred to as the “Run for the Roses.”

The winning horse becomes the only horse eligible to complete that year's Triple Crown, by running in and winning the two other legs of the series. The middle "jewel" is the Preakness Stakes two weeks later at Pimilco Race Course in Baltimore, and the final leg is the Belmont Stakes three weeks after the Preakness at Belmont Park in Elmont, N.Y.