I'm trying to get from Munich to Interlaken in as little time as possible. Ideally I would like to take an overnight train on the 31st of May but don't know if there even is one. The problem is I'm only going to be staying the 1st and 2nd in Interlaken and don't want to spend all day on the 1st as a travel day. Anyone have any good advice. Thanks.
For Munich to Interlaken, German Rail (bahn.de) shows an 11 hour connection (21:49-8:57) using four trains, one of which is a night train from Salzburg(0:44) to Zürich (6:20). Not much time on the night train. I really don't think you want to do that!
There is also a 6hr 26min connection leaving Munich at 18:34, changing in Zürich and Bern and getting into Interlaken Ost at 1 AM. You can get a fare as low as €39 for that one.
If you are not concerned about night train (sleeper, couchette) accommodations, there is a night train leaving Munich Ost at 1:10, going to Karlsruhe at 4:23 (3 hrs, just get a seat), leaving Karlsruhe at 5:56, changing in Basel at 7:47 and getting into Interlaken at 9:57. Or, you can leave Karlsruhe at 6:57 and go direct to Interlaken Ost at 10:57.