Freezing temperatures cut off the power on some lines, disrupting train traffic in several regions.
Internationally, traffic between St. Margrethen in St.Gallen and Munich was interrupted due to heavy snowfall. EuroCity trains between Zurich and Munich were canceled.
Before it resumes normal service, Swiss Federal Railways (SBB) must clear a thick layer of snow from trains and remove fallen trees from tracks, the company said on its website.
The train between Basel and Zurich airport will be canceled until Tuesday evening.
But SBB says it will resume most of its traffic on the main lines on Monday, though at reduced frequency.
Shorter train formations and longer journeys should also be expected in the next few days.
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How can you know ahead of time about any last-minute cancellations or delays?
The timetable is also constantly updated on the SBB Mobile App.
Any delays or last minute cancellations are indicated there in real time.
On Twitter, @RailService and @railinfo_cff provide information on possible disruptions as well.
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