Last minute 22 year old daughter and 51 year old mother-daughter trip to Europe June 27 (arrive noon in Munich) til mid July this year for 18 nights. We fly into Munich and out of Rome. Want to use public transportation instead of renting a car. We have been to Italy several times and need to spend one night in Bologna and 3 nights in Rome to visit friends at end of trip, otherwise we are open to suggestions and flexible on itinerary. From Rick's travel books we think we want to see the following highlights: Munich, Salzburg, Berchtesgaden, Rhine river valley (st. Goar and Bacharach), interlakken (gimmewald and Murren). Prague also looked interesting but having trouble with connections and wondering if would be better off seeing more of Germany, Switzerland or even Italian Lake District. We would appreciate any help with our trip that you can give us, especially public transportation. We have been looking mainly at trains but are open to bus and even budget air
I think the Rhine River is expendable from this plan. Prague would add more variety to the trip, for instance, and travel time Munich-Prague is about 5 hours each way, same as Munich-Bacharach. If you went east, you could circle through Munich-(Salzburg roundtrip/daytrip)-Prague-Vienna-Venice-rest of Italy.
Or do Munich/Salzburg/Bavaria and then do add a second stop in Switzerland, which should be glorious in July. If you can get a room, it's nice to stay closer to the mountains in Lauterbrunnen, Muerren, or Gimmelwald, instead of Interlaken. If you add the Pontresina/St. Moritz area, on the "Bernina Express route" then you can take regional trains south from there to Varenna on Lake Como (schedules only through Trenitalia.com or trenord.it, and may not all be published for July). Or you can take the "Golden Pass" route from Interlaken to the Montruex/Lausanne area; connections to Italy from there work fine, too.
Trains serve all your destinations, but will require some connections. Choose your destinations and plot them on a calendar before worrying about ticket prices or railpasses. How to Look Up Train Schedules Online gives you the DB train schedule link and tips for using it for the rest of Europe.