The station dates from 1895 .... and originally it was steam trains. You can see in the video on the walls, in height, holes .. it was the vents to evacuate the smoke. Now it is the station of the students ^^ .The university of the sorbonne is nearby During the extension to the north (it was a terminus for 75 years) in the 70's, the tracks and platforms had to be lowered by a few tens of cm, to prevent the tunnel from descending too steeply towards St Michel, the next station at the North. And even so ,the slope is above the maximum average for rail.
