The switch lever system is essential for directing trains on the tracks. During the 19th and most of the 20th century, the switchman’s life was very stressful. They had to prepare the path of trains which they could not yet see by pulling heavy levers. They had to run quickly from one lever to another and manoeuvre them with force, using their foot. While on the first floor of the switchyard, the lights came on and the telephone kept ringing. The Cité du Train-Patrimoine SNCF has preserved an old switchyard from Mulhouse station.