We are taking a family trip in July 2014. We are flying into Frankfurt (Main) and want to go to Lucerne, Interlaken and on to Paris. Can anyone recommend the best train to take as far as sightseeing, etc.? The only reason we are flying into Frankfurt is the possible countryside views as we travel to Lucerne. If the views are not sufficient, we have no problem flying into Zurich or another city. We want to spend one night in Lucerne and two nights in Interlaken. We then want to go to Paris and stay there for two nights as well. Any suggestions would be appreciated!.