|  Total 
        length: 19.9 
        km (17 km underground) - 29 stations
 Large-profile 
        line with ~100 m long platforms (6-car trains of F and H stock).  Line 
        U6 operates every 5 minutes through the day.
 Line 
        U6 was the first large-profile line when it opened in 1923. It runs along 
        Friedrichstraße, Berlin's major north-south axis in the city centre. 
        Initially the former Line C had two southern branches, but the eastern 
        branch from Mehringdamm to Britz-Süd was transferred to the new line 
        U7 in 1966.  As 
        with line U8, the stations in the city centre were skipped between 1961 
        and 1990, with the exception of Friedrichstraße, which remained 
        open to provide transfer to the West Berlin S-Bahn routes or allow certain 
        pedestrians to cross the border. In 
        the 1950s and 1960s, line U6 was extended at both ends to become Berlin's 
        busiest north-south line. The northern extension to Tegel includes a 3-station 
        elevated section. 30-01-1923: 
        Hallesches Tor - Stettiner Bahnhof (now Naturkundemuseum)08-03-1923: Stettiner Bahnhof - Seestraße
 19-04-1924: Hallesches Tor - Belle-Alliance-Straße (now Mehringdamm) 
        [- Gneisenaustraße U7]
 14-02-1926: Mehringdamm - Kreuzberg (now Platz der Luftbrücke)
 10-09-1927: Kreuzberg - Flughafen (now Paradestraße)
 22-12-1929: Flughafen - Tempelhof
 03-05-1956: Seestraße - Kurt-Schumacher-Platz
 31-05-1958: Kurt-Schumacher-Platz - Tegel (now Alt-Tegel)
 28-02-1966: Tempelhof - Alt-Mariendorf
 04-12-2020: 
        Französische Straße closed and replaced by Unter 
        den Linden
 From 
        7 Nov 2022 until mid-2025 the section Kurt-Schumacher-Platz - Alt-Tegel 
        is out of service for upgrading! 
         |