If I arrive by international train from abroad, what do I have to do? Are Swiss Travel System tickets valid on these trains?

No. Swiss Travel System tickets are valid only on the Swiss Travel System national route network. Separate tickets are required for international arrivals or departures. On the website of Schweizerische Bundesbahnen (sbb.ch), international arrival and departure tickets are available. Please inquire directly whit the SBB which ticket is best for your international journey.

Links

Timetables and tickets (SBB)