TheSüdostbahn (German,lit. 'South-Eastern Railway') – commonly abbreviated toSOB – is aSwissrailway company, and a1,435 mm (4 ft 8+1⁄2 in)standard gauge network inCentral andEastern Switzerland. It resulted from the merger of theoriginal SOB with theBodensee–Toggenburg railway (BT) at the end of 2001.

Südostbahn (SOB)

A SüdostbahnStadler FLIRT on theSeedamm
Native name	Schweizerische Südostbahn AG (German)
Company type	Jointlycantonal andfederally ownedAG/SA
Industry	Rail transport
Founded	1 January 2001; 24 years ago (2001-01-01) (retroactive)
Headquarters	St. Gallen , Switzerland
Key people	Thomas Küchler (CEO), Benedikt Würth
Revenue	CHF48.1276million (2021)[1]
Number of employees	815 (as of 2021)
Divisions	Passenger
Website	sob.ch

SOB rail network

Südostbahn (SOB) rail network
Overview
Dates of operation	1 May 1877–present
Technical
Track gauge	1,435 mm (4 ft 8+1⁄2 in)standard gauge
Electrification	100% 15 kV, 16.7 HzOverhead line
Length	111 km (69.0 mi)[1]

TheSchweizerische Südostbahn AG (Swiss South-Eastern Railway SA) is a small private railway jointly owned by thecantonal andfederal governments as anAktiengesellschaft (AG).^[2]

The rail network of the Südostbahn (SOB) consists of that formerly owned byBT innortheast Switzerland (betweenLake Constance andToggenburg):

• Romanshorn–St. Gallen St. Fiden line,
• St. Gallen–Herisau–Degersheim–Wattwil line, and
• (Wattwil–)Ebnat-Kappel–Krummenau–Nesslau-Neu Sankt Johann line,

and that previously owned by theoriginal SOB located predominantly inCentral Switzerland:

• Rapperswil–Pfäffikon SZ line,
• Pfäffikon SZ–Freienbach SOB–Wollerau–Samstagern–Schindellegi-Feusisberg–Biberbrugg–Altmatt–Rothenthurm–Biberegg–Sattel-Aegeri–Steinerberg–Arth-Goldau line, and
• Einsiedeln–Biberbrugg–Schindellegi-Feusisberg–Samstagern–Wädenswil line.

Since 2006, SOB also ownsWattwil station and the railway from Wattwil toEbnat-Kappel, which until then belonged toSBB CFF FFS. The railway stations ofRomanshorn,St. Gallen, andPfäffikonSZ, and the railway tracks between St. Gallen St. Fiden–St. Gallen, Wattwil (except railway station)–Rapperswil, and Arth-Goldau–Luzern are owned by Swiss Federal Railways, but areused by SOB for its services.

In total, the SOB network measures 128.9 kilometres (80.1 miles), and comprises the following lines:

• Romanshorn – St. Gallen St. Fiden (19.1 kilometres (11.9 miles))
• St. Gallen – Wattwil – Nesslau-Neu St. Johann (44.5 kilometres (27.7 miles))
• Rapperswil – Pfäffikon SZ (Seedamm) (4 kilometres (2.5 miles))
• Pfäffikon SZ – Arth-Goldau (34.6 kilometres (21.5 miles), including 6.1 kilometres (3.8 miles) common with Wädenswil–Einsiedeln)
• Wädenswil – Einsiedeln (16.7 kilometres (10.4 miles))

Theadhesion railway network spreads over mountainous terrain, with a maximumslope of 50‰ (5%) between Wädenswil/Pfäffikon SZ and Biberbrugg, and between Rothenthurm and Arth-Goldau. The lowest altitude on the SOB network is found atRomanshorn (399 metres (1,309 ft)a.s.l.), and the highest atBiberegg (933 metres (3,061 ft) a.s.l.), between Rothenthurm and Sattel-Aegeri. The highest elevation on the section between Nesslau-Neu St. Johann and St. Gallen is reached near Degersheim (798.7 metres (2,620 ft) a.s.l.).

The network is mostly asingle-track railway, with intermittentdouble-tracks (9.84 kilometres (6.11 mi) in total) present in sections where trainscross regularly. The entire network iselectrified since 1939.

The direct connection fromLake Constance (Bodensee) viaLake Zurich (Zürichsee) towardsLake Lucerne (Vierwaldstättersee), which follows the Alpine foothills, was achieved by numerous civil engineering works. These consist of a series ofviaducts and tunnels. Engineering structures account for one eighth of the total SOB rail network.^[2] They comprise:

• 177 bridges spanning a total of 4.2 kilometres (2.6 miles), and
• 19 tunnels through 8.5 kilometres (5.3 miles) of mountains.

One of the viaducts, the 99 metres (325 ft) high and 365 metres (1,198 ft) longSitter Viaduct (SOB) nearSt. Gallen Haggen, is the highest railway bridge in Switzerland. It is also the longest bridge on the SOB network and was built between 1908 and 1910. Other notable viaducts are theGlatttal Viaduct (296 metres (971 ft) long, 34 metres (112 ft) high) nearHerisau station, and theWissbach Viaduct (289.5 metres (950 ft) long, 63 metres (207 ft) high) betweenDegersheim andSchachen. Manybridges of the SOB network were constructed by BT.

The longest tunnel on the SOB network is the 3.5 kilometres (2.2 mi) longWasserfluh Tunnel betweenBrunnadern-Neckertal andLichtensteig, with 10.4‰grades. The tunnel was constructed between 1905 and 1910. The second longest tunnel is theBruggwald Tunnel between St. Gallen St. Fiden andWittenbach, having a length of 1.7 kilometres (1.1 mi) and a slope of 12‰. It was built between 1907 and 1910. Mosttunnels of the SOB network belonged to BT previously. The 8.6 kilometres (5.3 mi) longRicken Tunnel on theUznach–Wattwil line, used by the SOB operatedVoralpen Express andS4 service ofSt. Gallen S-Bahn, belongs toSwiss Federal Railways (SBB CFF FFS).

In the 1990s, the former Südostbahn (SOB) ordered four two-piece NPZ (Neuer Pendelzug;English: "new commuter train") sets(RBDe 566 + ABt), which were delivered from the first production series in 1995, bearing numbers RBDe 566 400-403. Initially, the SOB opted not to convert any intermediate cars for use with these trainsets. Thus, the SOBDVTs differed from those of the SBB CFF FFS by the addition of afirst class compartment. Themotor coaches of the NPZ sets, however, were identical to those of SBB CFF FFS. The SOB later converted several intermediate cars to elongate their trainsets (three-/four-car sets).

The NPZ first classcontrol cars (ABt) existed for the two types of RBDe 566 that SOB owned at that time (RBDe 566 071-076 exBT and RBDe 566 077-080 exoriginal SOB of the type also used by SBB CFF FFS). Until 2019, ninesecond class control cars (BDt) were used for theVoralpen-Express sets withRe 456,Re 446 orRe 420 (the latter occasionallyleased from SBB-CFF-FFS)locomotives. After the merger of the original SOB with BT, the four NPZ sets were repainted in 2003 in thelivery of the new SOB, with the sides of the vehicles painted light and dark gray, and the nose and border between side and roof painted red. They operated throughout the SOB network as RBDe 566 077-080.

The NPZ sets were later replaced byStadlerFLIRTEMUs (four-car-sets), delivered between 2007 and 2013 (RABe 526 041-526 063). The latter were painted in the most recent SOB livery: silver, with red window band, and light gray doors. Additional FLIRT-III four-car-sets were delivered between 2019 and 2021 (RABe 526 001-526 006). The FLIRT/FLIRT-III sets operate asS-Bahn service, but also as extension units during peak-hours onInterRegio lines, i.e., for thenamed trainsVoralpen-Express/Treno Gottardo/Aare Linth, for which newcopper-red paintedTraverso eight-car EMU sets (RABe 526 101/201-526 117/217) started operations between 2019 and 2021. Some of the FLIRT/FLIRT-III sets are named after mountain peaks along SOB operated lines. The names are indicated near the ends of the trainsets.

InSwitzerland, it is common customs to nameEMUs (e.g.SBB RABe 501,RABDe 500,RABe 514) andlocomotives (e.g.SBB Ae 6/6,Re 6/6,Re 450,Re 460). Several of Südostbahn's four-car EMUs are named after Swiss mountains. The name, along with a line drawing of the mountain'screst line and its highestelevation in meters above sea level (Meter über Meer, m.ü.M.), are indicated near the ends of the trainset. The table below summarizes all named SOB trainsets:^[3]

Südostbahn (SOB) operatesInterRegio (IR) services asnamed trainsVoralpen-Express,Treno Gottardo, andAare Linth. Due to theclock-face scheduling, the Swiss rail network offers passengers timely connections at most railway stations. Since 2018, most InterRegio lines in Switzerland are numbered and color-coded for more clarity.

From 1992 to 2013,Voralpen-Express (English: "Prealps Express") was jointly operated with theSwiss Federal Railways (SBB CFF FFS), and it continued as aregional train betweenSt. Gallen andRomanshorn. It is since operated solely by SOB, and the trains turn around in St. Gallen. Between 2013 and 2019,Voralpen-Express ran under its owntrain category (VAE). It is now again classified as InterRegio (unnumbered) after it was briefly categorized asPanorama Express (PE). The nameVoralpen-Express is still indicated onplatform displays and mentioned during train departure announcements at theplatform.

IRVoralpen-Express:Luzern –St. Gallen

Luzern –Luzern Verkehrshaus –Meggen Zentrum –Küssnacht am Rigi –Arth-Goldau –Rothenthurm –Biberbrugg –Pfäffikon SZ –Rapperswil –Uznach –Wattwil –Herisau – St. Gallen

Voralpen-Express runs mainly on tracks of the SOB network butuses tracks owned by Swiss Federal Railways between Lucerne and Arth-Goldau, and between Rapperswil and Wattwil (including the 8.6 kilometres (5.3 mi) longRicken Tunnel on theUznach–Wattwil line).

Treno Gottardo (Italian for "Gotthard train") is jointly operated by SOB andSBB CFF FFS and runs entirely on the network owned by the latter. It connects the city ofLocarno, in theItalian speaking part of Switzerland, alternately with the cities ofBasel andZurich, both located in theGerman speaking part of the country. Trains to/from Basel reverse direction at Lucerne (dead-end station). It was launched in December 2020, but trains turned around at Bellinzona until spring 2021 due to construction work between Bellinzona and Locarno at that time.^[4]

 Basel SBB –Locarno

Basel SBB –Olten – Luzern – Arth-Goldau –Schwyz –Brunnen –Flüelen –Erstfeld –Göschenen –Airolo –Ambri-Piotta –Faido –Lavorgo –Bodio TI –Biasca –Castione-Arbedo –Bellinzona –Cadenazzo –Tenero – Locarno

 Zürich HB –Locarno

Zürich HB –Zug – Arth-Goldau – Schwyz – Brunnen – Flüelen – Erstfeld – Göschenen – Airolo – Ambri-Piotta – Faido – Lavorgo – Bodio TI – Biasca – Castione-Arbedo – Bellinzona – Cadenazzo – Tenero – Locarno

Treno Gottardo follows the scenic route of theGotthard Railway. This "old route" crosses theAlps through the ca. 15 kilometres (9.3 mi) longGotthard Tunnel betweenGöschenen (1,106 metres (3,629 ft)a.s.l.) andAirolo (1,142 metres (3,747 ft) a.s.l.). It uses a series ofspiral loops andhorseshoe curves (partly in tunnels) to quickly gainaltitude, or to lose altitude on the other side of the tunnel, respectively. AllInterCity andEuroCity trains instead use the 57.09 kilometres (35.47 mi) longGotthard Base Tunnel since its opening in 2016.

The named trainAare Linth was launched in December 2021.^[5] It connectsChur, the capital ofCantonGrisons, with the Swiss capital ofBern. The trains reverse direction atZurichmainstation (Zürich HB), which is acul-de-sac. The train is named after theAare andLinth rivers, which it follows/crosses on its journey.Aare Linth is operated by SOB in cooperation withSBB CFF FFS; it runs entirely on the Swiss Federal Railways network.Stadler "Traverso" trainsets operate on this InterRegio line except duringrush hour, when higher-capacityrolling stock of SBB CFF FFS is used.

 Bern –Chur

Bern –Burgdorf –Herzogenbuchsee –Langenthal –Olten –Zürich Altstetten – Zürich HB –Thalwil –Wädenswil – Pfäffikon SZ –Siebnen-Wangen –Ziegelbrücke –Unterterzen –Walenstadt –Sargans –Bad Ragaz –Maienfeld –Landquart – Chur

In December 2024, the new named trainAlpenrhein-Express began operations using Stadler "Traverso"EMUs.^[6] It connectsChur withSt. Gallen. The train is named after theAlpine Rhine (Alpenrhein), a portion of theRhine. TheAlpenrhein-Express runs mainly over theChur–Rorschach railway line of Swiss Federal Railways, which follows the Alpine Rhine. This line was upgraded todual tracks prior to the opening of the service, allowing for a half-hourly InterRegio service. TheAlpenrhein-Express operates hourly, while another IR13 service of Swiss Federal Railways operates in between. The latter run between Sargans via St.Gallen to Zurich. The same trainsets used for theAlpenrhein-Express continue as S81 service of St. Gallen S-Bahn (see below), providing hourly direct services between Chur andAppenzell Ausserrhoden's capital Herisau.^[7]

 St. Gallen –Chur

St. Gallen –Rorschach –St. Margrethen –Heerbrugg –Altstätten SG –Buchs SG – Sargans – Bad Ragaz – Maienfeld – Landquart – Chur

As of the December 2023 timetable change,^[update] Südostbahn (SOB) operates the followingS-Bahn services in Central and Eastern Switzerland:^[8]

• Lucerne S-Bahn:
  • S31Arth-Goldau –Steinerberg –Sattel –Biberegg –Rothenthurm –Altmatt –Biberbrugg
• St. Gallen S-Bahn:
  • S4Rapperswil –Uznach –Kaltbrunn –Wattwil –Lichtensteig –Brunnadern-Neckertal –Mogelsberg –Degersheim –Schachen (Herisau) –Herisau –St. Gallen Haggen –St. Gallen –St. Gallen St. Fiden –Mörschwil –Goldach –Rorschach Stadt –Rorschach –Staad –Rheineck –St. Margrethen –Au SG –Heerbrugg –Rebstein-Marbach –Altstätten SG –Oberriet –Rüthi SG –Salez-Sennwald –Buchs SG –Sevelen –Sargans
  • S6Rapperswil –Blumenau –Schmerikon – Uznach –Benken –Schänis –Ziegelbrücke –Nieder- und Oberurnen –Näfels-Mollis –Netstal –Glarus –Ennenda –Mitlödi –Schwanden ( –Nidfurn-Haslen –Leuggelbach –Luchsingen-Hätzingen –Diesbach-Betschwanden –Rüti GL –Linthal Braunwaldbahn –Linthal, only during off-peak hours)
  • S17Sargans –Mels –Flums –Walenstadt –Unterterzen –Murg –Mühlehorn – Ziegelbrücke – Schänis – Benken – Uznach – Schmerikon – Blumenau –Rapperswil
  • S81St. Gallen – St. Gallen Haggen –Herisau
• Zürich S-Bahn:
  • S13Einsiedeln – Biberbrugg –Schindellegi-Feusisberg –Samstagern –Grüenfeld –Burghalden –Wädenswil
  • S40Einsiedeln – Biberbrugg – Schindellegi-Feusisberg – Samstagern –Riedmatt –Wollerau –Wilen bei Wollerau –Freienbach SOB –Pfäffikon SZ –Hurden –Rapperswil
• Not formally part of an S-Bahn network:
  • S27 (March shuttle)Ziegelbrücke –Bilten –Reichenburg –Schübelbach-Buttikon –Siebnen-Wangen (operates only Monday–Friday during peak-hours)

• Rail transport in Switzerland

• Official website(in German)
• Voralpen-Express website(in English)
• Treno Gottardo website(in English)
• Aare Linth website(in English)