We are arriving in Zurich on 9.18 and out of Frankfurt on 9.25. Taking a train from Zurich to Luzerne for 2 nights, then need help! Thinking of Interlaken for one or two nights, possibly Bern? Back up to Heidelberg for a couple nights? We love nature more than museums and like meandering around small towns to explore. Also, on possible 4 -5 days in Swiizerland, get a rail pass? We plan Mount Pilatus, lake boat rides, meandering depending on the weather!
Thank you for your recommendations.