the golden pass

check out the website Rome2Rio. "Golden Pass" refers to a specific train line that runs from Lucerne to Interlaken to Montreux. There are several trains on this route every day, in both directions.

http://www.eurail.com/trains-europe/scenic-trains/golden-pass

You can get off and get back on as often as you like if you have a railpass, otherwise you would buy local tickets. Except in high season, you shouldn't have trouble getting a seat so you don't need to buy a seat reservation, unless that makes you more comfortable.

The same company also runs the Chocolate and Cheese trains, and the funicular from Montreux to Rochers-de-Naye.

Go to www.sbb.ch, the Swiss national railroad. They have all the schedules and prices. Specify "via" Zweisimminen, Interlaken, and Brienz to get the correct routing.

There are "normal" trains that run on the same tracks and deliver you to the same places. I would not alter my schedule just so that you can sit on the train that has gold paint and big letters Golden Pass written on the side. If it's in the station waiting when you need to go then fine. Otherwise just catch a normal train.

The "Golden Pass"is not one train, it is four: Montreux - Zweisimmen - Spiez - Interlaken Ost - Luzern.
You have to change 3 time (Zweisimmen, Spiez and Interlaken Ost). It is also not just one train on this route. There are many trains per day on these routes, but one is designated "Golden Pass Express" and has special coaches with panoramic windows which you can book. Whichever train you take, the mountains are the same.

Sam is correct, go to www.sbb.ch for times, but be sure to add Zweisimmen, Spiez and Interlaken Ost in "via", or you will get the faster route around the alps.

Thanks, everyone!