The 1957 Giro d'Italia was the 40th running of the Giro d'Italia, one of cycling's Grand Tour races. The Giro started in Milan, on 18 May, with a stage and concluded in Milan, on 9 June, with a leg. A total of 120 riders from 15 teams entered the 21-stage race, which was won by Italian Gastone Nencini of the Leo-Chlorodont team. The second and third places were taken by Frenchman Louison Bobet and Italian Ercole Baldini, respectively.
Fifteen teams were invited by the race organizers to participate in the 1957 edition of the Giro d'Italia. The team size increased from seven to eight riders per team, which meant that the race started with a peloton of 120 cyclists. From the riders that began the race, 86 made it to the finish in Milan.
The Giro organisation invited five national teams (most of which for the duration of the Giro were sponsored by an Italian company) and ten Italian teams:
The "international" team was a combined Swiss-Luxembourgish team.
Reigning champion Charly Gaul was seen as a favorite to repeat as winner.
The route was revealed on 5 March 1957.
One jersey was worn during the 1957 Giro d'Italia. The leader of the general classification â calculated by adding the stage finish times of each rider â wore a pink jersey. This classification is the most important of the race, and its winner is considered as the winner of the Giro. There were no time bonuses in 1957.
A secondary classification was the mountains classification. For the first time in Giro history, the climbs were ranked in first and second categories. In this ranking, points were won by reaching the summit of a climb ahead of other cyclists. There were two categories of mountains. The first category awarded 10, 7, 5, 3, and 1 points, while the second distributed 5, 3, and 1 points.
There was an intermediate sprints classification. The first three riders at each intermediate sprint received points, 5 for the winner down to 1 for the third.
Also present was the piste classification, in Italian known as , a rebranding of 1956's . There were eight stages that ended on a velodrome, and the first three riders on those stages received points (5 for the winner, down to 1 for the third).
There was also one classification for the teams, based on stage positions: the stage positions of the three best riders per team were added, and the team with the lowest total rank was the best team. There was no jersey for this classifications.