Paris Métro Line 3 (French: Ligne 3 du métro de Paris) is one of the sixteen currently open lines of the Paris Métro. It connects Pont de Levallois–Bécon station in the near northwestern suburban city of Levallois-Perret to Gallieni, in the eastern suburban city of Bagnolet. After opening as the network's third line in 1904, it was subject to several extensions, including the major restructuring occurring of1971, where the line switched its easternmost section from Porte des Lilas to Gallieni, the abandoned section becoming Line 3bis.
With a length of 11.7 km (7 mi), Line 3 crosses Paris from west to east completely on the Rive Droite, serving the residential areas of the 17th arrondissement, the Gare Saint-Lazare, important stores and shopping centres, the Opéra Garnier, the former Parisian stock exchange house, the Place de la République, and the Père Lachaise graveyard. In 2017, it carried 101.4 million riders, making it the tenth busiest line of the Métro network.