Line 2, commonly called the orange line due to its color on the map, was one of the initial lines of the Montreal Metro when it started in 1966. It originally had 15 stations and went from Henri-Bourassa to Bonaventure. If line 1 was originally more centered around downtown, line 2 was including other boroughs from the start, going north to Le Plateau Mont-Royal, Rosemont-La Petite Patrie, Villeray-Saint-Michel-Parc Extension, and Ahuntsic-Cartierville.
In the 1980s, it was decided to expand to the West to Côte-Vertu but it was done gradually from 1981 to 1986. Therefore, many stations served as a temporary terminus, from Place Saint-Henri (April 28, 1980) to Snowdon (September 7, 1981) to Côte-Sainte-Catherine (January 4, 1982) to Plamondon (June 29, 1982) to Du Collège (January 9, 1984), until Côte-Vertu opened (November 3, 1986).This gradual extension doubled the lines' total stations to 28, and also brought the metro to Le Sud-Ouest, Côte-des-Neiges-Notre-Dame-de-Grâce and Saint-Laurent.On April 28 2007, there was a 3 stations extension to Laval at the Eastern part of the line, making Montmorency the new terminus, even if some trains still use Henri-Bourassa as a terminus during rush hour, which is why a 3rd platform was made at Henri-Bourassa. The total number of stations is now 31.
Rolling stock was initially the MR-63 made by Canadian Vickers until the MR-73 made by Bombardier debuted in 1976. Then in 2016, the MPM-10 (called Azur) made by Bombardier and Alstom entered service and by 2018, only Azur trains remain on the line.
The frequency of trains is 3 to 5 minutes at peak hours, 4 to 10 minutes at non-peak hours, and 6 to 12 minutes on weekends.
Trains are stored at St-Charles Garage at Henri-Bourassa station and Montmorency Garage at Montmorency station, but the STM is currently building a new garage at Côte-Vertu station that will be better equipped to welcome Azur trains. There is also a workshop called Youville between Crémazie and Sauvé. From there, trains can connect to line 5 between Parc and De Castelnau. The other workshop is the Duvernay workshop between Lionel-Groulx and Georges-Vanier, where trains can switch with line 1. Other places where trains can switch lines are Berri-UQAM (line 1 and 4) and Snowdon (line 5).
There are 4 transfer stations. Berri-UQAM transfers with lines 1 and 4, Lionel-Groulx with line 1, while Jean-Talon and Snowdon transfer with line 5.
The majority of the stations have side platforms. Only Lionel-Groulx and Snowdon have island platforms (with the other line).