The Diamond Stakes is a Listed flat horse race in Ireland open to thoroughbreds aged three years or older.
It is run at Dundalk over a distance of 1 mile, 2 furlongs and 150 yards (2,149 metres), and it is scheduled to take place each year in September or October.
The event was formerly classed at Listed level and contested on turf over 1 mile and 2 furlongs.
The Diamond Stakes moved to Dundalk in 2008, and since then it has been run on a Polytrack surface over 1 mile, 2 furlongs and 150 yards.
[2] The Diamond Stakes was added to the Breeders' Cup Challenge series in 2009, with the winner earning an automatic invitation to compete in the Breeders' Cup Marathon.