Of the lines that were not built, two lines should have crossed the inner city, and one would have extended the Gürtel line along the southern Gürtel road to Südbahnhof railway station.
Af de linjer, der ikke blev bygget, skulle to have krydset den indre by, og en skulle have forlænget Gürtel-linjen langs den sydlige Gürtelstraße til Wien Südbahnhof.