While travelling Europe during 1872 and 1873, an American called Colonel Meriwether Lewis Clark, Jr. attended the famous Epsom Derby horse race held annually in England since 1780, as well as the Grand Prix de Paris, which was organised by the French Jockey Club. On his return to the United States, Clark, who was grandson of William Clark of Lewis and Clark fame, founded the Louisville Jockey Club and Driving Park Association to raise money to build racing facilities on the outskirts of the Kentucky city. Two relatives of his, John and Henry Churchill, leased the land for the track, which from 1883 was known as Churchill Downs.
On 17th May 1875, an estimated ten-thousand people gathered at the track to watch the first Kentucky Derby. Jockey Oliver Lewis rode the colt, Aristides, to victory in the 1.5 mile race. This was the same distance as the Epsom Derby and Grand Prix de Paris; however, the Kentucky Derby was run over its current distance of 1.25 miles from 1896.
Like the races that inspired it, the Kentucky Derby became a regular fixture on the social calendar, and from 1952 it also became an annual television event. On 3rd May that year, CBS broadcast the race coverage of their Louisville affiliate television station, WHAS, to the nation. The winner was Hill Gail, ridden by Eddie Arcaro and trained by Ben A. Jones.
For more details of this race see the official website page about the 78th Kentucky Derby.
