Railway service in Switzerland
The S21 is a regional railway service of the Zürich S-Bahn of the Zürcher Verkehrsverbund (ZVV). The service operates at peak hours between and over the Wettingen–Effretikon railway, supplementing the regular service, which continues west to .
At Zürich HB, trains of the S21 service usually depart from ground-level track () 18.
Route.
The service operates on weekdays during peak hours; there are a total of eight trains in each direction per day. Inbound trains in the morning and outbound trains in the evening bypass . Trains usually depart from (or arrive at) one of the surface platforms of Zürich HB. The S21 calls at the following stations:
History.
The S21 designation was previously used for service from Zürich to over the Thalwil–Arth-Goldau railway; this is now provided by the . The current S21 began running with the December 2015 timetable change.
Rolling stock.
As of the December 2022 timetable change,[ [update]] most services are operated by Re 450 class locomotives pushing or pulling double-deck passenger carriages.
References.
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