Advice on which Rail card for our trips.

Hi Sally,

The 4-day Swiss Saver Flexi Pass would be an option, especially since you only pay for one person for a two-person pass as there is a 2-for-1 promo. The pass includes 4 days of free traveling and (mostly 50%) discounts on all trips on non-free travel days between the first and last free travel day. You can use one of the free days for the Glacier Express. Another one could be used to go to the Jungfraujoch (free until Wengen, 25% discount on the remaining leg) and do free boat trips on the way back to Thun. The pass also allows you to do some free train trips instead of traveling by car. There are some beautiful routes near Thun so I can certainly recommend doing so. One example is the Lötschberger train from Thun via Spiez, Kandersteg and Goppenstein to Brig. Further details on the pass can be found here.

An alternative is the Swiss Half Fare Card: 50% discounts on nearly everything for a month. Also, there is a 2-for-1 promotion on the Regional-Pass Bernese Oberland. It does not include the Glacier Express and it's only for 7 days though.

One more tip: be sure to travel from Davos via Filisur to Brig, rather than via Landquart. The scenery is more attractive. The route via Landquart is quicker but not part of the Glacier Express.

Have fun!