Just a few months after opening, a serious accident occurred on the suburban line, when on 6 January 1899 at 4:00 am the locomotive 30.17 was accidentally led onto a stump track shortly after leaving Heiligenstadt station. The train, which consisted of 85 empty freight cars, then overturned the buffer from Tulln to Hütteldorf-Hacking and crashed into Gunoldstraße, which ran six to seven meters below. The locomotive driver suffered heavy injuries and the heater suffered minor injuries. Exactly this accident situation at the same place repeated itself on the 20th of February 1928, whereby in turn no casualties were to be lamented. For Stadtbahnunglücke the Viennese Voluntary Rescue Society in the year 1900 specially a special railway ambulance car in enterprise, which was stationed in the station main customs office.