I would like to a train from either Bern or Zurich, Switzerland to Berlin, Germany. Any suggestions and how long should I plan for that trip. Also, would it be feasible for me to rent a car to explore Germany or us the rail system? I have a week in Germany and would like to see Berlin, Frankfurt and Munich area any suggestions for this leg of the trip? Thanks in advance Theresa
First of all there are direct ICE trains from Zurich, Interlaken (Bernese Oberland) and Basel to Berlin. But the journey time is 8+ hours. There are plenty of ICE trains from your Swiss cities to Frankfurt and you could stay in the region for a few days. From there it's an easy 4 to 5 hours train journey to Berlin. Alternatively there are a few trains from Zurich to Munich. If you have a week in Germany only and you already have seen mountains in Switzerland you might want to focus more on Frankfurt to Cologne (Rhine river, Mosel river) and then Berlin (at least 3 days).
If your German trip is going to be centered around cities, you're better off without a car. There are places where having a car makes sense, but cities aren't them.