The Zürich S-Bahn (German: S-Bahn Zürich) system is a network of rail lines within the ZVV area (geographically, within the entire canton of Zürich, portions of Aargau, and minor outlying areas such as Rapperswil).
The entire ZVV S-Bahn network went into operation in May 1990, although many of the lines were present beforehand.
The S-Bahn network is numbered, but numbering is rather sporadic, with several missing lines (e.g. S19, S20). The lines are numbered from the S1 to the S43.
Double decker train near Andelfingen (August 2006)
A train from the Zürich S-Bahn (Summer 2002 image)
S43 ran between Rüti and Wald (near Rapperswil) and had only three stations and was in fact a limited service of S43. It has been replaced by a bus route.
Projected future lines: Several lines are projected with the opening of the 3rd underground station at Zurich HB (2013). Map
Notes:
[1] Rafz and Niederweningen alternate every hour.
[2] Services restricted by time only.
[3] Seuzach and Winterthur Seen alternate every hour.
[4] International service: Stops in stations outside Switzerland.