Opened in 1980, it currently has 20 stations and a total length of 17.2 km (10.7 mi), from Karlsplatz to Seestadt.

After the tunnel was completed in 1966 with a length of 1.8 kilometres, it ran from Vienna Secession to Friedrich-Schmidt-Platz.

As a result, U2 was extended to the Ernst Happel Stadium in 2008, to Aspernstraße in 2010, and finally to Seestadt on October 5, 2013.

[8][9] In late 2017 it was announced that construction on the new line would start in 2018, with entry into service planned for 2024.

In addition, the trains were retrofitted with plastic seats, video surveillance and warning lights that had signalled the door closing.