Light rail system in Stuttgart, Baden-Württemberg, Germany
The Stuttgart Stadtbahn is a semi-metro system in Stuttgart, Germany. The Stadtbahn began service on 28 September 1985. It is operated by the Stuttgarter Straßenbahnen AG (SSB), which also operates the bus systems in that city. The Stuttgart Stadtbahn is successor system of a tram network ("Straßenbahnen") that characterized the urban traffic in Stuttgart for decades.
The network of the Stadtbahn covers much of Stuttgart and also reaches the neighbouring towns of Remseck am Neckar, Fellbach, Ostfildern, Leinfelden-Echterdingen and Gerlingen (clockwise). Currently, the Stuttgart Stadtbahn system is made up of fourteen main lines (U1-U9, U12-U15, U19), a special event line (U11) and two temporary lines during construction site, serving 203 stations, and operating on of route. In 2014, the Stuttgart Stadtbahn carried 174.9 million passengers.
Route network.
Current lines.
As of 2024[ [update]], the Stuttgart Stadtbahn system consists of:
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The U6, U7 and U12 lines run Monday to Saturday during the day as double sets as 80-metre long trains. The event line U11 and the special event services on the U5 run as double sets when required. All lines except the U5 and U8 run every ten minutes during the day during their operating hours.
Development of the route network.
Stuttgart Stadtbahn, now all , developed out of a traditional tramway system, which in Stuttgart was .
In 1961 the city council of Stuttgart decided that a general modernisation of the municipal tram system was needed; in central areas, tram track would be relocated underground, and in peripheral areas it would get new tracks that would be separate from road traffic. Concurrent proposals for a new completely underground subway (U-Bahn) were rejected in 1976. At the same time, it was decided to modernise the existing tram infrastructure and change from metre gauge to the standard gauge. For this reason, tracks were initially converted to mixed-gauge, on which old trams (SSB GT4, built 1959–1965) could run as well as new metro cars (SSB DT 8, in regular service since 1985).
In 1989, the light rail lines were given new numbers U1, U3 and U14 to distinguish them from the S-Bahn and tram lines. The E-line to Cannstatter Wasen and the stadium was renamed to U11 in 1994.
Network 2011.
The SSB changed the route of some light rail lines at the timetable change on 12 December 2010. The north branches of the lines U5 and U7 were exchanged, so that the U5 now goes to Killesberg and the U7 to Mönchfeld. Likewise, the U4 runs—as 25 years ago—from Berliner Platz on the previous route of the U2 to Hölderlinplatz, while the U2 runs instead to Botnang. The change connects outer branches with equally high volumes. The large residential area of Zuffenhausen/Rot/Freiberg/Mönchfeld is now served by double sets on the U7 lines, eliminating the previous overcrowding. The U2 also now serves two heavily frequented outer branches, where an expansion of capacity is being considered.
Line U12 operated until 2013 between Möhringen and Killesberg (in the peak hour: Vaihingen–Killesberg). On the Möhringen–Vaihingen section, it partially replaced the U6, which has been operating from Möhringen since 11 December 2010 to the Fasanenhof-Ost industrial area. Since 11 December 2011, the U15 line has also been running on the newly built section between Zuffenhausen and Stammheim.
Network 2013.
With the opening of the new section of the line north of the Löwentorkreuzung to Hallschlag on 14 September 2013, the route network was changed. The previous section of the U15, from the Stadtbibliothek stop on Nordbahnhofstraße to the Löwentor crossing, has since been served by the U12, which runs from there to Hallschlag. The U15 has since run on Heilbronner Straße directly to Pragsattel. From now on, Killesberg will only be served by the U5 every 20 minutes.
Network 2016/2018.
The lines planned in the context of Stuttgart 21 require a new Staatsgalerie railway station to be built and the tunnel between Staatsgalerie and the adjoining tunnel. The Staatsgalerie–Charlottenplatz and Staatsgalerie–Hauptbahnhof sections of the line were interrupted and rebuilt over seven and a half years. 
The Staatsgalerie–Charlottenplatz section was closed from May 2016 until December 2017 ("Network 2016"). The U1 and U2 lines were diverted via the Hauptbahnhof, the U4 line only ran as far as Neckartor with a turnaround at the Staatsgalerie stop. The U11 ran in both directions via the inner-city loop with a turnaround at Charlottenplatz. In order to maintain the connection between the Charlottenplatz stop and the northern branch of the U4 to Hölderlinplatz (there is no connection from Hauptbahnhof at Berliner Platz), the additional lines, U21 (Charlottenplatz–Südheimer Platz) and U24 (Charlottenplatz–Hölderlinplatz) were introduced.
From December 2017 until December 2023, the Staatsgalerie–Hauptbahnhof section was closed ("Network 2018"). The U9 was routed via Charlottenplatz to Heslach Vogelrain and supplemented by the additional line U29, which connected to the Hauptbahnhof, which can only be reached from the north, with the actual terminus of the U9 at Vogelsang (in peak hours in Botnang). The U14 line was routed via the inner-city loop to the Hauptbahnhof and was supplemented by the additional line U34 until summer 2023, which ran from Vogelsang to Südheimer Platz (if the S-Bahn main line was closed during peak hours, it also continued to Vaihingen Bf).
For the 2018 network, it was initially planned that the U14 would run from Mühlhausen via the Leuzeknoten and Bad Cannstatt to Neugereut instead of into the city center, where it would relieve the U2 and increase its traffic on its more frequented Bad Cannstatt–Neugereut section. The U11 was planned to be used in regular service for the connection to the city center.These plans were abandoned after a trial run from 17 October 2016 to 13 April 2017 in favour of the U19 reinforcement line, which finally began scheduled operations on 16 October 2017. It runs between Neugereut and Neckarpark and increases the frequency of the U2 on the section in question to approximately every five minutes. In addition, the U34 was to start in Heslach and go to the Hauptbahnhof instead of Vogelsang. The end point of the U9 would have been at Südheimer Platz instead.
With the timetable change on 9 December 2017, as part of the closing of the gap on the U12 between Hallschlag and Wagrainäcker, the U14 was withdrawn to Mühlhausen and the U12 was operated with double sets to its previous terminus in Remseck-Neckargröningen.
With the timetable change in December 2018, the new supplementary line U16 (Giebel–Fellbach) also began operations. It offers additional capacity during peak hours on the heavily used sections: Fellbach–Bad Cannstatt, Bad Cannstatt–Pragsattel and Pragsattel–Giebel. The U13, which previously ran to Giebel during peak hours, was withdrawn as far as Feuerbach Pfostenwäldle.
Network 2024.
With the timetable change on 10 December 2023, following the commissioning of the new tunnel between the State Gallery and the Hauptbahnhof, it was possible to return to the original Stadtbahn network, before the restrictions imposed by Stuttgart 21 (networks 2016 and 2018). In addition, the U1 and U14 lines swapped their southern and central branches as a preliminary measure for the capacity increase of the U1. In the future, the U1 will run via the inner-city loop (Hauptbahnhof–Berliner Platz–Rotebühlplatz) and on to Heslach Vogelrain (if the S-Bahn main line is closed during peak hour, initially also on to Vaihingen) and the U14 via Charlottenplatz and Rathaus to Vaihingen Bahnhof. The line swap in the city centre is due to better utilisation of vehicle capacity and the connection of the Neckar valley around Mühlhausen with the city centre by the U12.
The U11 again ran anticlockwise through the inner city loop and the additional lines U34 (already discontinued due to a lack of staff) and U29 were made obsolete by the return of U9 and U14 and thus discontinued. In addition, the U8 will now take over the U15 services to Heumaden during the afternoon peak hour and will be intensified to a ten-minute cycle between Vaihingen and Heumaden during this time.
Current light rail system.
The Stadtbahn system runs over of rail track, and of rail line, covering of route. (The Stuttgart rail system also encompasses a rack railway (Line 10), a funicular (Line 20), and a weekend heritage tram line (Line 21).) In the city centre as well as in other densely built-up districts of the city, the Stadtbahn runs underground. The Stadtbahn uses the "U" logo like the underground systems "(U-Bahnen)" in other German cities. However, here the "U" does not stand for "untergrund" (underground) but for "unabhängig" (independent, meaning independent of other traffic infrastructure). Outside the densely built up areas, the Stadtbahn runs on the surface, often along roads with level crossings, though on a separate right-of-way. However some trains, especially U15 line's trains, operate partially with street running and share space with other traffic.
Rolling stock.
The system's fleet consists of 224 light rail vehicles, all of which are variants of the DT8 model. The system operates on standard gauge track, and is electrified at 750 volts DC.
Current fleet:
Color.
Since the coat of arms of Stuttgart shows a "black", rampant horse on a "yellow" or golden field, the Stuttgart Stadtbahn (as well as all the buses and the last old trams) comes in yellow with black or dark blue window frames.
Hours of operation.
The Stuttgart Stadtbahn operates from 04:00 - 01:00.
Most routes are served by two or more lines in the city centre, so there is a train every few minutes at most stations.
Fares and ticketing.
The Stadtbahn is part of the regional transport cooperative, the Verkehrs- und Tarifverbund Stuttgart (VVS; Stuttgart Transit and Tariff Association), which coordinates tickets and fares among all transport operators in the metropolitan area. Besides the Stadtbahn, these include the SSB's bus networks, together with the Stuttgart S-Bahn, operated by a subsidiary of Deutsche Bahn AG (DBAG), and DBAG's Regionalbahn regional train services within the VVS area.
History.
The Stuttgart Stadtbahn succeeded a tram network that previously dominated urban transport. In 1961, the local council decided to move the rail network in the city centre underground, to switch to new, more powerful vehicles and to separate it from motor traffic in the outer areas as far as possible.
The first tunnel stop was built in 1966 at Charlottenplatz in coordination with the reconstruction of the intersection of federal highways B 14 and B 27, where the routes of the central valley longitudinal (roughly north-south) lines (at that time parallel to the B 14) intersect with the valley transverse lines (parallel to the B 27). A tunnel between Neckartor and Marienplatz (running close to the B 14) was completed in 1972. All tunnel routes and stops were already built with a clearance profile suitable for the planned standard gauge vehicles and the track system was laid out with a third rail for standard gauge. The new vehicles were to be high-floor and the stops were given high platforms.
In the mid-1970s, the introduction of an underground railway was discussed, which would take over the new tunnels, until the decision was made in 1976 to gradually replace trams with a more efficient light rail system. By 1978, Königstrasse and the Hauptbahnhof as well as the sections to the then Universitat (the former site of the university, now Börsenplatz) and Türlenstrasse (now Stadtbibliothek) stations were tunnelled, followed by the Rotebühlplatz stop by 1984, the shell of which was already built in 1978 as part of the S-Bahn construction, and the Siemensstrasse tunnel between Pragsattel and Feuerbach station.
The Stadtbahn network is designed in such a way that it could be converted to a U-Bahn at any time if the financial means were available. Contrary to popular belief, the U in the line name does not stand for underground railway, but for "unabhängig"—independent (from road traffic).
Conversion of tram to Stadtbahn operation.
The main criteria for the expansion of the Stadtbahn system were the conversion to standard gauge and the development of a bidirectional vehicle so that the turning loops at the end of the line could be eliminated. In addition, barrier-free access to the trains should be possible without having to climb steps. The DT 8 light rail vehicle, specially developed for Stuttgart, took these requirements into account.
Both systems had to be operated alongside each other for a long period of time with interim solutions. The routes intended for light rail operations were converted to a dual gauge track. The third rail on the inside was later gradually removed where metre-gauge trams were no longer running. Some sections will remain permanently as