The U2 is an underground line in Nuremberg, opened on 28 January 1984 and the last station along the line to open was Flughafen (Airport) in 1999. The line is about long and has 16 stations; the termini are Röthenbach and Flughafen. Since 2010 all trains in regular operations are run driverless. At the stretch between Ziegelstein station and Flughafen station is the longest interval between two stations in the network and the only single track section on any subway line in Germany (both stations have two platform tracks, but the track between the two is single track without passing loops). Overview In the following, the direction is from southwest to northwest in line with the direction in which the line was built. The route begins in the southwest of Nuremberg at Röthenbach station, at the western end of a three-track parking and turning system, and continues east along the Schweinauer Hauptstraße under the Main-Danube Canal and the :de:Südwesttangente highway (southwestern tangential road) to the station Hohe Marter. This station is the longest in the Nuremberg subway network with and replaces the two abandoned tram stops Friesenstraße and Schweinau, which were formerly located at the two present-day subway exits. The route continues under Schweinauer Hauptstraße to Schweinau station and St. Leonhard station, which, due to its location in the middle of Schweinauer Straße, is completely elastic so as not to give off the vibrations caused by driving to the surrounding houses. Next is the Rothenburger Straße station beneath the Frankenschnellweg (A73). Rothenburger Straße station marks the beginning of the shared trunk line between U2 and U3 and is also served by S1 of the Nuremberg S-Bahn. Consequently, a lot of interchanging traffic uses this station. The last part of the southern half of the route runs in a curve under the Obere Kanalstraße and then leads in a right arc to the Plärrer station, where the U2 meets the U1. The Plärrer is an old interchange point for all kinds of transportation and was served by Germany's first railway and at times over a dozen tram lines. As of 2022 it is served by all Nuremberg subway lines and two (out of five) Nuremberg tram lines. After the station Plärrer the route runs under the Frauentorgraben to Opernhaus station. During construction of this station which is close to the former city wall, the former moat which had been filled in