At Gien it starts following the river Loire upstream along its right bank, in a generally southern direction.

It passes through the Monts de la Madeleine, northern foothills of the Massif Central.

It crosses the Loire between Roanne and Le Coteau, where the shorter line to Lyon via Tarare branches off.

It continues south, parallel to the Loire, passing through Feurs and along Andrézieux-Bouthéon, where it meets the line from Clermont-Ferrand via Montbrison.

At Givors on the river Rhône it turns north, finally arriving in Lyon after 492 km.

In 1834 the line was extended in northern direction from Saint-Just to Le Coteau, near Roanne.