[1][2] The event was originally contested over 880 yards and then switched to the metric conversion of 800 metres in 1971.
Throughout much of the history of the event it was contested by women only because the men competed in the 1,500 metres freestyle.
The most successful male and female competitors in the history of the event are Alan Kimber and Daniel Jervis with three titles each, and Rebecca Adlington and Rebecca Cooke with six titles each.
Cooke has won the most consecutive titles, all six coming between 2000 to 2004.
The current champions (2024) are Tobias Robertson and Amelie Blocksidge, their first titles in both cases.