as S2 heading for
Niedernhausen passing
Hofheim-Lorsbach
The early years Plans for a rail connection between the central rail station (Hauptbahnhof) in Frankfurt and the Hauptwache, the central commuter destination in the city, were started in the early 1960s. Construction work on the project started in 1969. During the construction phase, some rearrangements were carried out to the commuter network in the area around Frankfurt, including creation of a link line between
Bad Soden am Taunus and Niederhöchstadt. In 1978 the first section of the "Citytunnel" of the Rhine-Main S-Bahn was opened, with all lines sharing the tunnel between Hauptbahnhof and Hauptwache. The initial system, which lay entirely to the north of the river
Main, comprised the following lines: •
S1:
Wiesbaden Hbf –
Höchst –
Hauptbahnhof –
Hauptwache •
S2: Niedernhausen – Höchst – Hauptbahnhof – Hauptwache •
S3:
Frankfurt-Höchst – Bad Soden –
Frankfurt West – Hauptbahnhof – Hauptwache •
S4:
Kronberg – Frankfurt West – Hauptbahnhof – Hauptwache •
S5:
Friedrichsdorf – Frankfurt West – Hauptbahnhof – Hauptwache •
S6:
Friedberg – Frankfurt West – Hauptbahnhof – Hauptwache lines in 1980 In 1980, two further lines were added to the network, made possible by construction of a new rail bridge over the river
Main: •
S14:
Wiesbaden –
Mainz –
Flughafen – Hauptbahnhof
(main arrivals hall) •
S15: Flughafen – Hauptbahnhof – Hauptwache Completion in 1983 of a 600m long easterly extension of the Citytunnel, as far as Konstablerwache, improved the opportunities for train turnaround in the tunnel. At this stage lines S1–S6 and line S14 were extended to Konstablerwache, while the S15 was rerouted to the main arrivals hall of the Hauptbahnhof.
Later Developments In 1990 the Citytunnel was extended, adding the underground stations Ostendstrasse and Lokalbahnhof to the system, along with the overground station Frankfurt Süd. All the lines (with the exception of the S15) were extended to Frankfurt Süd, while the S5 and S6 were further extended a short time later to a new station at Stresemannallee, south-west of Frankfurt Süd. In 1992, S1 and S2 trains were diverted to the new Mühlberg underground station, the first station in the direction of Offenbach. This left the S3, S4, S5 and S6 serving all the stations between Hauptbahnhof and Frankfurt Süd, a situation which still pertains to this day. The S14, which is now the S8, also served all of these stations. In 1995, the newly instituted RMV increased train frequency from a 20/40/60 minute schedule (depending on the time of day) to the 15/30/45/60 minute schedule which is still used in the system. The S15 ceased operations at this stage. Also in 1995, a new underground alignment through the city of Offenbach was opened, assisting the rerouting of the S14 (renamed the S8) through Mühlberg to
City-Tunnel Offenbach and Hanau. The S1 was also extended as far as Offenbach, while the S2 returned to serving Frankfurt Süd. In 1997, the routes of the S5 and S6 were shortened slightly, so that they travelled only as far as Frankfurt Süd, while the S3 and S4 were extended to Darmstadt and Langen. The section of the S3 between Höchst and Bad Soden im Taunus also ceased to be served by S-Bahn trains. In 1999, the S8 was effectively divided into two lines, the S8 and S9, both of which travel between Hanau and Wiesbaden via
Bischofsheim. The S8 continues to travel through the centre of Mainz, while the S9 travels via
Mainz-Kastel. This arrangement means that it is possible to travel between Wiesbaden, the capital of the state of
Hesse, and Frankfurt, the state's largest city, by three different routes. In the same year, a new station on lines S3-S6 was opened in the Frankfurt fairground (
Frankfurt Messe station). In 2002, a new S-Bahn line, the S7, between Frankfurt Hauptbahnhof (main arrivals hall) and
Riedstadt-Goddelau was added to the system (replacing the regional train line on the northern part of the
Mannheim–Frankfurt railway). Due to a shortage of capacity in the Citytunnel, these trains are not currently able to reach Frankfurt's inner city. At present, these trains do not operate on a 30-minute schedule because of several ICE lines that operate on the same tracks. In 2003 the
Rodgaubahn, a commuter rail system serving Offenbach and its environs, was incorporated into the Rhine-Main S-Bahn system. This resulted in the S1 being extended from Offenbach Ost to Rödermark-Ober Roden, while the S2 was also rerouted from Frankfurt Süd to serve Offenbach Ost and all stations to its new terminus in Dietzenbach. The current system has an almost 5-minute frequency for services between Frankfurt and Offenbach Ost and an actual 5-minute frequency for services between Frankfurt Hauptbahnhof and Frankfurt Süd. The group of lines S1, S2, S8 and S9 all share 10 stations, as do the group of lines S3, S4, S5 and S6. All the lines, with the exception of the S7, share 5 stations. Initially this arrangement gave rise to some considerable delays caused by poorly functioning signalling. To some extent this has been allayed by routing every second westbound S2 train in peak times to
Offenbach am Main (Hauptbahnhof) and every second eastbound S2 train in peak times to the main arrivals hall of the Frankfurt Hauptbahnhof, rather than running these services through the Citytunnel. Reconstruction of the signalling technology in the Citytunnel enabled all westbound S2 trains to travel all the way to Niedernhausen at a frequency of 15 minutes in 2010. Since 2015 a new signal tower for the Citytunnel is installed at Frankfurt Hauptbahnhof which is going to replace the original signal tower operating since 1978 in 2018. Therefore, it is necessary to close the tunnel several times between 2015 and 2018 for between two and six weeks each, mostly during school holidays. The times of service closure are also used to modernize the stations in the tunnel. From July 31 to August 18, 2006, the mainline tunnel between the main station and Konstablerwache was completely closed to exchange 30 switches. On May 13, 2007, the served by the S2, new breakpoint Frankfurt Zeilsheim was opened, on 31 October 2008, operated by the S3, single-track breakpoint Schwalbach North. For the timetable change 2017/18, a continuous night traffic was introduced on weekends. Due to nocturnal blockages of the City Tunnel, the railways go in a first phase at night on modified lines: • S1: Wiesbaden Hbf - Hochheim (Main) - Frankfurt-Höchst - Frankfurt (Main) Hbf - Frankfurt (Main) South - Offenbach (Main) Main Station - Rödermark-Ober-Roden • S3: Frankfurt (Main) South - Langen (Hesse) - Darmstadt Hbf • S4: Kronberg (Taunus) - Eschborn - Frankfurt (Main) West - Frankfurt (Main) Hbf • S5: Friedrichsdorf - Bad Homburg - Oberursel (Taunus) - Frankfurt (Main) West - Frankfurt (Main) Hbf • S8: Wiesbaden Hbf - Mainz central station - Rüsselsheim - Frankfurt airport - Frankfurt (Main) Hbf - Frankfurt (Main) south - Offenbach (Main) central station - Hanau central station From August 2018, the start of operations of the entire night traffic in the Citytunnel is planned. From December 2018 the S8/S9 will be 24/7 through the Citytunnel with a 30-minute frequency between 1:00am and 4:30am from Frankfurt Flughafen Regionalbahnhof to Konstablerwache (1:11am/4:11am from Konstablerwache to Frankfurt Flughafen Regionalbahnhof) and a 60-minute frequency between 12:49am and 3:49am from Wiesbaden Hbf and Hanau Hbf (1:46am/3:46am from Hanau Hbf to Wiesbaden Hbf) ==Bridges==