The Sihltal Zürich Uetliberg Bahn AG () – commonly abbreviated to SZU – is a public transport company and network in the Swiss canton of Zurich. The network comprises the Uetliberg and Sihltal railway lines, operated by S-Bahn services S4 and S10, a cable car and several bus services of Zimmerbergbus.

The SZU is jointly owned by the city of Zurich (32.6%), the municipalities of Adliswil, Langnau am Albis, Horgen, Thalwil and Uitikon (6.8%), the Canton of Zürich (23.8%), the federal government (27.8%), and other parties (9%). It is constituted as an Aktiengesellschaft (AG) or public company.

History The history of the SZU dates back to two separate companies, which built the two railways that now make up the SZU. The first of these companies was the (), which opened its line from Zurich Selnau railway station in Zurich to near the summit of Uetliberg mountain, Zurich's Hausberg, in 1875. This was followed in 1892 by the company (SiTB, ), which opened a line from Zurich Selnau station to Sihlwald. In 1897, this latter line was extended to Sihlbrugg and a connection with the Thalwil–Arth-Goldau line of the former Swiss Northeastern Railway (NOB).

In 1920, the became bankrupt and was liquidated. Two years later, the was taken over by the (BZUe). In 1923, the was electrified using the direct current (DC) system, whilst the following year the was electrified using alternating current (AC).

In 1932 the SiTB took over the management of the BZUe, but the two companies remained in existence until 1973, when they were merged to form the SZU. In the meantime, in 1954, the SiTB had taken over the management of the Adliswil-Felsenegg cable car.

In 1990, the two lines were extended from their previous joint terminus at Zurich Selnau (until then a surface station) to a new terminus below Bahnhofplatz, adjacent to Zürich Hauptbahnhof (), named . This extension involved the construction of a new rail tunnel from Selnau to Zürich HB, and a new underground intermediate station adjacent to the former terminus, . The underground platforms used at Zürich HB were already in existence, having been built prior to 1973 for a U-Bahn scheme that was ultimately rejected by voters. Once the new extension had been opened, the former terminus at Selnau was redeveloped and little evidence of it is now visible.

In 1995, the company took over responsibility for bus services in parts of the district of Horgen through which the runs.

In 2006, after 109 years, the stopped servicing and , previously the penultimate station, became the new terminus.

Rail network The SZU continues to operate the original and lines. The two lines share a common double-track section between and , with the final approach being in a tunnel, partly under the Sihl river. A dedicated pair of underground platforms (tracks/ 21 and 22) are used at Zürich Hauptbahnhof (Central Station), with no rail connection to the rest of the station. The platforms are physically connected via the ShopVille underground mall.

Also operated is a connecting line from Giesshübel to the Swiss Federal Railways at , although this is normally only used for freight traffic. It is occasionally also used by passenger trains, for example if the regular route From Zürich HB to via becomes temporally inoperable. In all, the SZU network measures : as part of the (including the Wiedikon–Giesshübel line) and of the .

Both railway lines are constructed to and both are electrified using the standard Swiss mainline system of overhead lines at 15 kV 16.7 Hz AC. Until 2022, the was electrified using overhead lines at 1200 V DC. In order to avoid conflict on the shared railway section, the used an overhead line offset from the centre of the track, and its cars were equipped with specially designed, laterally displaced pantographs.

Rolling stock The SZU uses the following rolling stock on its railway lines:

Sihltalbahn (S4) 6 Locomotives Re 4/4 542–547 7 Control car (rail) Bt 971–973, Bt 984–987 6 Intermediate single deck cars BD 281–285, B 293 6 Intermediate double deck cars B 271–276 2 Re 456 Double deck trains (DPZ): Re 456 551, 552, B 231, 232, 241, 242 and Bt 951, 952 (two sets taken over from SBB, type Re 450) 8 Low floor double deck cars (NDW).

Uetlibergbahn (S10) 6 SZU Be 510 class EMUs ordered from Stadler in 2010,, details in German on http://www.bahnonline.ch. that entered service in 2014, equipped for dual voltage operation with movable pantograph

Operations Railways

The passenger services on the two lines form part of the Zurich S-Bahn, with the service over the to Sihlwald branded as the S4 and the branded as the S10. The also includes a nighttime service during weekends (SN4). At Zürich Hauptbahnhof (Zürich HB), all SZU services depart from the subsurface station located below Bahnhofplatz.

Zurich S-Bahn:

Nighttime S-Bahn ––

Cable car The cable car Luftseilbahn Adliswil-Felsenegg (LAF for short or commonly called Felseneggbahn) is operated by the SZU. Its valley station is within walking distance above station. The cable car leads to Felsenegg, a popular hiking area.

Bus The Zimmerbergbus lines in the district of Horgen, which provides a network of including 201 stops, is also operated by the SZU.Zimmerbergbus: Facts & figures The buses connects SZU stations in the Sihl Valley with railway stations on the western shore of Lake Zurich located on the Lake Zurich left bank railway line.

Tariffs The SZU was a founding member of the Zürcher Verkehrsverbund (ZVV) in May 1990 and the standard ZVV zonal fare tariffs apply to its services.

See also List of railway companies in Switzerland Public transport in Zurich Rail transport in Switzerland

References

External links

Luftseilbahn Adliswil-Felsenegg Zimmerbergbus