the kentucky derby ˈdɜrbi is a horse race held annually in louisville kentucky united states on the first saturday in may capping the two week long kentucky derby festival the race is a grade i stakes race for three year old thoroughbreds at a distance of one and a quarter miles 2 km at churchill downsn may 16 1925 the first live radio broadcast of the kentucky derby was originated by whas and was also carried by wgn in chicago on may 7 1949 the first television coverage of the kentucky derby took place produced by wave tv the nbc affiliate in louisville