Mar 5, 2017 - 4:55 PM
in reply to bright629
Hi Bright629 and welcome to MySwissAlps!
You are correct, no seat reservations required or needed in Switzerland (with our without your Swiss Travel Pass). You can simply hop on any train you wish and show the pass when asked.
Please note if you plan on visiting some mountains such as Jungfraujoch, the Swiss Travel Pass only covers a portion of the trip (25% discount from the town of Grindelwald or Wengen to Jungfraujoch).
The pass will cover trains to these towns from elsewhere in Switzerland so you just need to buy a pass from those towns to Jungfraujoch.
Take a look at the where its valid page for the STP here.