17 cities in 35 days is probably doable, but it’s not realistic and it won’t be much fun. Packing up and moving every other day is grueling. My suggestion:
1. Aim for an average of 3 days per city to accommodate the travel time involved. Paris, London and Rome need at least 3 days — 4 is better when you figure travel time.
2. Limit one night stays to 1 a week
3. You’ve got some seriously long distances here which makes point 1 even more important. Check rail schedules at: http://reiseauskunft… My rules of thumb: Train ride less than 5 hours, take the train. Train ride 5 to 7 hours, fly or take the train — whichever’s cheaper. Train ride over 7 hours, fly unless it’s prohibitively expensive. Take an overnight train if you can’t find a cheap flight.
4. Limit the total of flights and overnight trains to an average of 1 per week, with no more than 2 in any 7 day period.

Your budget is doable assuming it’s $3,500 each and it doesn’t include your flight and your railpass.

Since I think you’ll need some flights to make a widely scattered itinerary work, figure out which legs you want to fly and buy the tickets while cheap ones are still available, then figure out which railpass is best. I doubt that a consecutive day pass will be the best deal if you fly some of the legs.

It says your COMBINED budget is $3500. If that means each of you are spending $1750 for 35 days, it ain’t gonna happen unless you plan on only eating bread and drinking tap water, not to mention spending a few nights under bridges. If you’re each taking that much money you’ll be fine. Fifty dollars a day is hardly anything. Does it include airfare and railpass? Are you planning on museums, day trips or anything else like that? As OldLady says, limit your one night stays. Newbies always think they’ll be fine and they never are when they try to squeeze too much in. Why four days in Madrid? Why Marseilles at all? I’d suggest you take a day from Florence and add that to Nice. Venice you only need one day to see, get rid of the other day and put it somewhere else. Don’t go to Brussels. Once you give us some more info we’ll give you more.

You might be able to save some money by getting a different rail pass. I originally had the idea to use a consecutive Global Pass, but after sitting down, plotting out my route and finding the price of point to point tickets, I found I could save about $300 by using a Select flex pass.

I too would advise to rethink your itinerary. I have done whirlwind travel before and I was exhausted after 2 weeks, nevermind a whole month! You need to remind yourself that there will be chances to come back and you don’t need to cram everything into one trip. If you could leave Spain for another trip, you could take the night train from Paris to Nice, and spread those days out into the rest of your trip.

As you can see above you have received different advice from 3 different people. Take in all suggestions, mull it around, look at positives and negatives and than do what the hell you want to do. Ask yourself why you are going to Marseilles (skip it). Why Berne? Go to Interlaken for the SWISS ALPS, Balmer’s Hostel, Canyoning Adventures, Paragliding and Skydiving out of a helicopter. Take a day trip up to Gimmelwald and Murren or stay overnight at Hostel Gimmelwald for Million Dollar Views! Fussen can be done on a day trip from Munich and can’t miss Munich beer gardens or Mike’s Bike Tour in Munich. Heidelberg was nothing special. I have enjoyed staying the the castle hostel in Bacharach am Rein just north of Mainz and if you have a Global Pass (Consecutive days) you can take a river cruise down to Rhein River and view many castles. Get off at St. Goar and walk around and take the train north to Amsterdam. You also left at CINQUE TERRE – the best way to experience Italy. Look up GoBuzzs…. for photos. Stay in a air conditioned hotel in Nice and be sure to go to Wayne’s Bar in Old Town by 9:30pm Squeeze down to the pit area and when the live band starts, jump up and dance on the tables! Always a great time!
Have the time of your life!