The IAU 24 Hour World Championship is an annual international 24-hour run competition which succeeded the IAU World 24 Hours Track Championships and it incorporates the IAU 24 Hour European Championships.
The IAU 24 Hour World Championship is an annual international 24-hour run competition organised by the International Association of Ultrarunners (IAU). Preceded in 2001 by the IAU World 24 Hours Track Championships, as a track running event, this competition became the IAU World 24 Hours Challenge in 2003. The competition has often incorporated the IAU 24 Hour European Championships  a continental event which pre-dates the global competition, having first been held in 1992. 
