Which darts tournament is played in legs where every leg starts and ends on a double?

The World Grand Prix is the darts tournament famous for requiring players to start and finish every leg on a double.

This format is called double-start, double-finish. A player’s score does not begin until a double or the bullseye is hit, and the leg must also be completed with a double or bullseye. The rule makes early scoring more difficult than in the standard straight-start format.

The tournament was first held in 1998 and became one of the Professional Darts Corporation’s major events. It is traditionally played in Ireland and has been staged at venues including the Citywest Hotel in Dublin and Leicester’s Morningside Arena.

The World Grand Prix is often confused with the World Matchplay because both are major PDC ranking tournaments. The distinctive double-start rule, however, is the feature most closely associated with the World Grand Prix.