The line runs in its own section of the roadway of these boulevards between the 15th and 13th arrondissements of Paris, allowing it to connect Pont de Garigliano and Porte d'Ivry in an average of 26 minutes. It carried 25 million passengers in its first year of operation, averaging 100 000 every weekday, and 70 000 at the weekends; numbers have steadily increased ever since. In 2009, further work began to extend the line to the east and north, with the extension fully opening on 15 December 2012. Two separate lines were constructed to ensure the service's reliability: the existing line was extended to Porte de Vincennes and renamed T3a; a second line (T3b) initially connected Porte de Vincennes to Porte de la Chapelle. An extension of the latter to Porte d'Asnières has opened on 24 November 2018.