Jul 14, 2016 - 11:54 AM
Hi kochumon, welcome to MySwissAlps!
Yes, theoretically that's possible for most trains. Note that it's not common in Switzerland though, and not required for the vast majority of trains. For some (regional trains) and mountain transportation it's not even possible. Assuming you'll be using a Swiss Travel Pass, you can just board and get out wherever and whenever you like. You'll reduce that flexibility by making seat reservations, which are valid for specific trains with specific departure times only.
Further information can be found at www.myswissalps.com/tr ain/reservations. If you do want to make reservations, please use the appropriate links listed at www.myswissalps.com/tr ain/reservations/price.