My wife and I are taking our 19 y.o. niece on her first train trip through Europe for two weeks in early September. She has been on a cruise through Med from Rome and along south of France and northwest Italy. We are planning only four stops, with starting in Paris for four days (wife and I have been twice), and ending for two full days in Venice (twice as wife and I as well).
I am a bit torn with lengthy train trips to see great sites for her and new sites for us. I am considering a north / northeast (Belgium) and then south trip (Prague / Vienna / Zermatt), or south (Lyon??) and then east (Switzerland mountains). Based on schedules, not long trips from Paris to Belgium / South France, but next two legs have 10+ hours no matter how I look at them. Trains are really a must to show her that experience and break down the travel barrier of traveling by train.
Would anyone have suggestions on what is best and worth the 10+ hour train rides? Thank you and Happy New Year to all.