It is a handicap race, and it is scheduled to take place each year during the Cheltenham Festival in March.
The County Hurdle was established in 1920, and its inaugural winner was Trespasser, ridden by George Duller.
During his career O'Brien recorded a total of twenty-three victories at the Cheltenham festival.
For many years the County Hurdle was traditionally the last race to be run at the Festival.
However, a new running order was announced ahead of the 2009 meeting, and it is now the second race on the final day.