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.
Zürich Underground Railway
In the 1970s "U-Bahn" project, the first line would have led from Dietikon via Schlieren, Zürich main station, Oerlikon and Opfikon to Zürich airport, including two short branch lines to Schwamendingen and Kloten. The two most important development axes of the agglomeration, Limmattal and Glatttal, would have been joined onto the network. The line would have been 27.5 km long, 14.8 km of which would have been underground. At a later point in time the construction of two more lines was planned. In spite of initial optimism the project was rejected in a referendum by the voters in the Canton of Zürich. Some parts of the lines, which had been built as preliminary work for the Underground that was never realised, are used today as the Milchbuck-Schwamendingen tram tunnel and as the terminus of the Sihltal-Zürich-Uetliberg-Bahn.