Zurich Airport
Zürich Airport railway station is located underneath the "Airport Centre". The station has frequent Zürich S-Bahn services, plus direct InterRegio, InterCity, and Eurocity services, to many places including Basel, Bern, Biel/Bienne, Brig, Geneva, Konstanz, Lausanne, Lucerne, Munich, Romanshorn, St. Gallen, and Winterthur. There are some 13 trains per hour to Zürich Hauptbahnhof, Zürich's main city centre station, with a journey time of between 10 and 15 minutes. By changing trains at Hauptbahnhof, most other places in Switzerland can be reached in a few hours.
Chur–Rorschach railway
Since 13 December 2009, two of the three daily EuroCitys to and from Austria have been replaced by Railjet services. This saves a total of 40 minutes running time between Zürich and Vienna, due, among other things, to having faster turnarounds in Buchs. The third train, the former Transalpin service, was also replaced by a Railjet service in June 2010, but, unlike the first two, runs as two coupled sets. Nine day and night trains a day connect Zürich with Austria, all with stops in Sargans and Buchs. The section from Rorschach to St. Margrethen is served four times a day by a EuroCity service on the Zürich–Munich route.
Rheintal Express (REX) services now run between Chur and St. Gallen every hour. Between Sargans and Rorschach, line S4 St Gallen S-Bahn services operated by Südostbahn also run every hour on a circular route with stops at all stations. Between Altstätten and St. Gallen the line is served by lines S1 and S2 of the S-Bahn. Overall, this results in two trains per hour between St. Gallen and Altstätten and three between Heerbrugg and St. Gallen. On the Sargans–Chur section the good connections from Zürich on two InterCity services and a RegioExpress are supplemented by the S12 (Sargans–Chur) service.
Freight traffic is heavy between Sargans and Buchs, because this is the transit route to the Vorarlberg and to the rest of Austria. The trains from France (Mulhouse) and the Limmattal marshalling yard (west of Zürich) to the Hall in Tirol marshalling yard use the route through the Buchs border crossing. The crossing at St. Margrethen is only used by trains to and from the Wolfurt marshalling yard. The Buchs marshalling yard serves the whole Swiss Rhine valley.
Since 2004 DB Cargo has been operating freight trains from Stuttgart Kornwestheim via the electrified Lake Line and then via Rorschach and St. Margrethen to the Wolfurt marshalling yard to avoid the use of diesel locomotives on the Lake Constance Belt Railway and the Ulm–Friedrichshafen railway.