Hello Thorntons,Thanks for the additional info. This offer for the Regional-Pass Bernese Oberland is valid from September, so that might suit your needs. The trip to Geneva is partly covered, as you can see on the associated map. Still, this is the cheapest option for you.
I just realized you need to hurry if you want to make use of the offer, as it is only available online and you're traveling soon. Shipping details and ordering options are on the Regional-Pass page.
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