Thanks again, Chris. I was vaguely aware of the Regional Pass, but didn't realise it covered such a large area! The furthest they're likely to want to go is somewhere like Interlaken, so they could travel to the edge of the regional zone and pick up a ticket for the last leg.

This will do just fine; I'll do them a little gift card with a print-out of the map, and buy them the pass when they come over for their spring/summer visit, to take best advantage of the boats.

Great - another one ticked off the gift list! Thanks for your guidance.

kodokan