Dec 30, 2015 - 9:54 AM
Welcome to MySwissAlps! What you read about the Bernina Express is certainly true. All the information is here: myswissalps.com/ berninaexpress.
I would suggest to take a train to Lugano. Then the Bernina Express bus to Tirano, and finally the Bernina Express train to Chur or St. Moritz, depending on how/where you would like to spend the rest of your week.
Which pass is most suitable depends on your itinerary. So you'd best create a detailed itinerary first, and select a pass based on that as explained here: myswissalps.com/train/ ticketspasses/practica l/ chooserailpass. If I had to guess right now, I would say an 8-day Swiss Travel Pass would be the best choice. That's what most people do when traveling around the country for a week. You'll find all the details here: myswissalps.com/ swisstravelpass. Be sure to watch the video for a quick intro. Most passes can be purchased from 6 months before the travel date.
This page is helpful too: myswissalps.com/ plantrip/doityourself. Note that there are rail packages as well, if you don't want to do all the planning yourself: myswissalps.com/ railholidays.