It is run at Ascot over a distance of 1 mile (1,609 metres), and it is scheduled to take place each year in June.
The event was established in 1843, and it was originally contested on a right-handed course over 7 furlongs and 166 yards.
The inaugural running was won by Knight of the Whistle, with a triple dead-heat for second between Bourra Tomacha, Epaulette, and Garry Owen.
The race's distance was shortened to 7 furlongs and 155 yards in 1930, and it was extended to its present length in 1956.
It is one of three perpetual trophies at the meeting, along with the Gold Cup and the Queen's Vase, which can be kept permanently by the winning owners.