The classic cycle races are the most prestigious one-day professional road cycling races in the international calendar. Some of these events date back to the 19th century. They are normally held at roughly the same time each year. The five most revered races are often described as the cycling monuments.
For the 2005 to 2007 seasons, some classics formed part of the UCI ProTour run by the Union Cycliste Internationale. This event series also included various stage races including the Tour de France, Giro d'Italia, Vuelta a España, Paris–Nice, and the Critérium du Dauphiné Libéré. The UCI ProTour replaced the UCI Road World Cup series (1989–2004) which contained only one-day races. Many of the classics, and all the Grand Tours, were not part of the UCI ProTour for the 2008 season because of disputes between the UCI and the ASO, which organizes the Tour de France and several other major races. Since 2009, many classic cycle races are part of the UCI World Tour.