Itinerary suggestions for Switzerland-Italy-Spain for my Parents. Help Please !!

If they go to Spain from Italy, they should fly. That's a grueling train trip. Also I suggest they'l get better answers if they post here themselves.

31st of what (March, April May)? 2nd to 7th of what month? What will they be doing from 31st xxxx to 2nd yyyy?
The only Torgon I can find is a small village in canton Valais with a bus connection from Aigle in the Rhône valley. Obscure, why are they going there?

You want a place to stay for 4 nights, 7th to 10th June? Luzern is a good choice, also Jungfrau region.

"They are also willing to get a rental car while in Torgon." - how are they getting to Torgon?. Once they get down the hill to Aigle station, train will take them to anywhere in Switzerland.

"Further they want to go to Italy. How to get there?" - where in Italy? It is a big country. The answer is probably train, and you can look up trains on the train company websites, once you decide where in Italy. Possibly fly if you want to go to southern Italy. Italy borders Switzerland, you can cross the border by any method you want, even on foot (I've done it)

"Can you please recommend a itinerary ?" - What are they interested in? Read a guide book
"Also the train routes?" - that is decide by where they are going.
"Should they take a euro rail pass?" - probably not. Trains in Italy are cheap.
"What are the towns they should stay in ?" - read a guide book.

Sorry, but all your questions are too vague. YOU (or your parents) need to research, read guide books and decide where they want to go.
Once your parents have decided, and want to know details of how to do what they want, ask specific questions and you are more likely to get answers.

What amazes me is why so many people that post here for itinerary assistance plan trips to Europe with places to visit that are not geographically close.

Switzerland, Italy and Spain are all wonderful places, but considering the primary places to visit in Italy are not near Switzerland I would recommend for this trip eliminating Spain.

Sorry, but touristy places abound in all these countries, especially in the Summer months.

One of my favorite places in Switzerland is Interlakken. You can venture out from this centrally located lake town. You can go up to the Youngfrau and ski in the summer on the glacier. You can check out much of central Switzerland with its amazing scenery.

For Italy, for a first time visit, I recommend the big three, Venice, Florence and Rome. For only 8 days, however, it is tough to spend enough time in each with only 8 days.

For Spain, I don't recommend spending 8 days in Barcelona, but the nearest major city to visit is Madrid or Valencia, some distance away.

If you stick to your three country plan, you might consider visiting Milan, Venice and Florence, after Switzerland, then move on to Spain (another option for a three country plan is to visit the Provence part of France instead of Spain).

I am at a loss to understand how one decides to spend ~11 days in Switzerland, 8 each in Italy and Spain and have no idea where they want to go and what they want to see.

Further they want to go to Italy. How to get there?

If northern Italy, a train may be the better choice; elsewhere flying may be the choice

From Italy to Spain - fly

Oh Karan, you should really have a word with your parents.

Hi Karen. These guys are right. It is a bit all over the map. If they are in the Switzerland area and Italy there are closer things to see than trekking over to Spain. I am an American living in several places in Europe for the past 20 years and have travelled here extensively. I would be happy to help lay out an itinerary that would provide lots of places without lots of travel. Just contact me and I will be happy to draft something for them. This form is a bit short to be able to lay it all out.