I have travel plans that involve traveling by train from Zurich to Freiburg (Germany) and back. Will there be any Customs & Immigration check related delays during border crossings ?
Where exactly are the checks done ?, on the train or at some border station ?
BTW, I am a U.S. citizen so Visas are not required.
Thanks.

I haven't had my passports checked on the train in years. I've gone from Zurich to Munich dozens of times. No check.

Passports/ID cards are checked on board the running train between Basel Badischer Bahnhof and Freiburg (if they are checked at all). The border police people hop on in Basel, walk through the whole train during the approx. half an hour trip and hop off in Freiburg, and vice versa on the way back. This won't cause any delays; if there's trouble they'll make that person get off at Freiburg resp. Basel.

Thanks for the response. I have a tight schedule and wanted to factor in any delays that are to be expected.

In my travels, if there was a check, the border officials got on at one stop, did a little checking, and got off at the next stop. Unless there was some kind of irregularity, there was no delay in the train schedule. I have never been impeded time wise.

I've seen Customs folks with dogs sniffing bags several times at Swiss borders - mainly with Italy it seems.

Since Suisse is not in the EU or Schengen Accords it still has border formalities.

Next Jan i believe they will join the Schengen group which has largely abolished border formalities for the average traveler at least.