左岸
Line C was opened on 26 September 1979, following the construction of a new tunnel connecting the Gare d'Orsay railway terminus (now Musée d'Orsay) with the "Invalides", terminus of the Rive Gauche line to Versailles, along the banks of the Seine. Services operated between Versailles-Château-Rive-Gauche – Invalides – Quai-d'Orsay, branching to Massy – Palaiseau, and Juvisy – Dourdan / Saint-Martin d'Étampes. At that point the line was named the "Transversal Rive Gauche".