Upvote:0
It will depend entirely on how quickly and how cheaply you wish to travel between these locations. Bus is usually your cheapest option, but also generally the slowest. Trains can be a little or a lot more expensive depending on whether you take the local (usually slower) trains or the high-speed (obviously faster) trains. Flying may be a faster and cheaper option for long distances but you need to factor in the travel time and expenses to and from airports, waiting time in airports etc. If you can give some more details on your budget and planned travel pace I can probably give you some more specific routes, times and prices.
Upvote:1
Switserland is amazing by train. The EU has a great deal in place to travel by train through all countries.
You may only need to reserve seats but this is a great way to travel cheaply while still being able to see the country side. The countries you named all have excellent train services so I would not feel the need to consider airplanes.
Upvote:2
This past summer, we took the direct TVG train from Paris to Interlaken - it's quick, easy, and relaxing. Then we took an overnight train from Interlaken to Paris. However, note that you'll have to pay a decent supplement even if you have a rail pass. We were hoping to take the slower option from Paris to Switzerland, but were unable to and couldn't find anyone who spoke English well enough to help us figure it out (sadly, I don't speak French). I'd advise you to be prepared for that and have a good idea of what you want to do before you head to the ticket counter.
I can't help you with the Vienna to Munich part, but I would guess that train would be your best option once again.
Upvote:7
Travel from Paris to Montreux, on the shores of the lake Geneva. From there take the scenic Golden Pass Line to Interlaken. In theory it is possible to do this in one day. However, I would advise you to split the journey and travel from Paris to Geneva or Lausanne on day 1 and then continue to Interlaken on day 2. If you don't like this option, you can take a direct TGV from Paris to Interlaken. This journey takes less than 6 hours. The usual route from Paris to Geneva or Lausanne also involves travel on high-speed (TGV) trains. If you are using a railpass and you want to avoid the supplement, note that there is an interesting, albeit slower, option from Paris to Switzerland.
Travel from Interlaken to Zurich (2 hours) and then from Zurich to Vienna on a daytime Railjet (+- 8 hours). This is a scenic route too, hence the advice to travel by day. You can do this in one day. The most scenic part is on the beginning. You might also consider a stop-over in Salzburg, as the Zurich-Vienna Railjet stops there. There is also a night train from Zurich to Vienna. This option is interesting if you are on a tighter schedule.
From Vienna to Munich takes you more or less 4 hours on a Railjet. This train stops in Salzburg too, in case you are interested.