and Interlaken? We will be staying with friends in Zurich in July, and will be taking many day trips (Luzern, Rapperswill, etc.). I would love to go to back to Thun and Interlaken, which I visited about 20 years when I was in college. Is it something that is easy to do (train) or will we need a car? Can one or the other be done in a day trip, or would we have to stay overnight?