the route of this new section runs parallel to those of above-ground transportation that were especially crowded. as a result, line 10 saw a rapid increase in use, however its route to the rive gauche did not respond well to the needs of passengers and therefore many used line 10 as a way to make connections to other lines, particularly line 5 at "place d'italie" and line 12 at "sèvres-babylone" to continue on to destinations on the rive droite. the western section sèvres-invalides remained sparsely traveled.