Just wanted to confirm, if I have the Swiss Rail Pass and I am traveling from Zurich to Interlaken, all I need to do is just board those trains? I don't need reservations? All I would do is show them the rail pass.
I do understand I will need to make reservations/ticket and pay extra to make it up to Jungfraujoch. How early do you recommend making those reservations? Weather varies so much I would hate to buy a ticket to early and not have a good day for site seeing,
I didn't make reservations for the Jungfraujoch and just got on the first train that fitted for my schedule up from Wengen. It was quite early but not the first. I don't go up mountains unless I know that the summit is clear and that it has a reasonable chance of staying that way or nearly so for my duration. I personally see no benefit in getting those sorts of things ahead. I'd rather queue at the right time.
After your Swiss Rail Pass is validated, yes just hop on any train from Zurich. Via Luzern and Brünig is considerably more scenic. Via Bern is a little faster.
Correct, just get on the train, noting where you have to change trains.
I do understand I will need to make reservations/ticket and pay extra to make it up to Jungfraujoch.
"Need" is a strong word. Wait until you know the weather will be good and take an early train.
You don't need to have reservations for any Swiss train (except the 4 extra named tourist trains - Glacier Express etc.). You just need a ticket. For the trains a Swiss Pass covers, that is your ticket so just get on.
For the Jungfrau or any other mountain railway, as Nigel says don't buy a ticket until you know the weather will be clear.
