The first Giro d'Italia was held in 1909, and the 2009 route was designed to commemorate the 100th anniversary, though interruptions due to World War I and World War II meant this was only the 92nd race.
Milan, which had for years been the city in which the Giro concluded, was the site of a ten-lap criterium on the same circuit that began the first Giro d'Italia.
Every city that hosted a stage start or finish in the first Giro was visited in 2009 with the exception of Genoa, although Arenzano (in the province of Genoa) hosted the finish to stage 11.
The 11th stage also went over the Passo del Turchino, a climb used every year in the classic cycling race Milan–San Remo.

The tenth stage was planned to mimic stage 17 of the 1949 Giro d'Italia, which was won by Italian cycling legend Fausto Coppi en route to the overall victory.
That route originally included the Col d'Izoard, a climb in France which has been featured in the Tour de France numerous times.
Race organizers were forced to alter this stage to cover only the Italian side of the Alps rather than also visit France, as there were concerns over radio communication in the area, and the roads stood the risk of landslides.
It was subsequently made longer than first planned, with an additional, shorter climb added.
Stages 10 and 16, the latter of which went over Monte Petrano and two other first-category climbs, were both called the race's queen stage.

The route received a small amount of criticism for failing to include any well-known and especially difficult climbs such as the Passo del Mortirolo or Monte Zoncolan, instead including stages featuring multiple climbs with lesser ascents.
Race director Angelo Zomegnan responded to the criticism by saying, "I won't follow the philosophy that the selection of climbs has to be determined by their names."

The 21 stages of the 2009 Giro d'Italia were divided into five categories: one team time trial, seven flat stages, four intermediate stages, seven mountain stages and two individual time trials.
The type of stage together with the average speed of the winner decided how much time each cyclist would be allowed to finish that stage before being eliminated from the race.
The first Giro d'Italia was held in 1909, and the 2009 route was designed to commemorate the 100th anniversary, though interruptions due to World War I and World War II meant this was only the 92nd race. Milan, which had for years been the city in which the Giro concluded, was the site of a ten-lap criterium on the same circuit that began the first Giro d'Italia. Every city that hosted a stage start or finish in the first Giro was visited in 2009 with the exception of Genoa, although Arenzano (in the province of Genoa) hosted the finish to stage 11. The 11th stage also went over the Passo del Turchino, a climb used every year in the classic cycling race Milan–San Remo.
The tenth stage was planned to mimic stage 17 of the 1949 Giro d'Italia, which was won by Italian cycling legend Fausto Coppi en route to the overall victory. That route originally included the Col d'Izoard, a climb in France which has been featured in the Tour de France numerous times. Race organizers were forced to alter this stage to cover only the Italian side of the Alps rather than also visit France, as there were concerns over radio communication in the area, and the roads stood the risk of landslides. It was subsequently made longer than first planned, with an additional, shorter climb added. Stages 10 and 16, the latter of which went over Monte Petrano and two other first-category climbs, were both called the race's queen stage.
The route received a small amount of criticism for failing to include any well-known and especially difficult climbs such as the Passo del Mortirolo or Monte Zoncolan, instead including stages featuring multiple climbs with lesser ascents. Race director Angelo Zomegnan responded to the criticism by saying, "I won't follow the philosophy that the selection of climbs has to be determined by their names."
The 21 stages of the 2009 Giro d'Italia were divided into five categories: one team time trial, seven flat stages, four intermediate stages, seven mountain stages and two individual time trials. The type of stage together with the average speed of the winner decided how much time each cyclist would be allowed to finish that stage before being eliminated from the race.
2009 Giro d'Italia