In addition, the Paris region is served by a light rail network of nine lines, the tramway: Line T1 runs from Asnières-Gennevilliers to Noisy-le-Sec, line T2 runs from Pont de Bezons to Porte de Versailles, line T3a runs from Pont du Garigliano to Porte de Vincennes, line T3b runs from Porte de Vincennes to Porte de la Chapelle, line T5 runs from Saint-Denis to Garges-Sarcelles, line T6 runs from Châtillon to Velizy, line T7 runs from Villejuif to Athis-Mons, line T8 runs from Saint-Denis to Épinay-sur-Seine and Villetaneuse, all of which are operated by the Régie Autonome des Transports Parisiens, and line T4 runs from Bondy RER to Aulnay-sous-Bois, which is operated by the state rail carrier SNCF. Who operates these lines