Switzerland and Germany Trip Final Plans and Need Transportation Expertise Please

When is this? I ask because there are some train lines under repair.
No one is ever ready to leave the BO. Two nights is hardly enough. I'd maximize your time there. Have a wonderful trip!

Thank you - in a few weeks. I’m thinking of extending BO - doing Lucerne only one night or not at all? Then train to Bern for a night, then on to Germany. Realizing it is not ideal that we are there for a short time, we also love exploring.

Bern is on a direct route toward Heidelberg and Frankfurt. Plus Bern is reported to be a great town to visit (I only changed trains there). Zurich might come under the heading, "Great place to live, but not so much to visit".

If this is for this Fall, Heidelberg is a good option as it avoids Mannheim where the rail reconstruction is going on.
Right now, this looks straight forward with train changes in Basel and Karlsruhe, getting you to Heidelberg in 3 3/4 hours.

Okay thank you, another question - what train app do i use to buy Bern - Heidelberg? Not SBB - at least I can’t nail it down. Thank you for your help!

We just did two nights in Zurich and thoroughly enjoyed it. I don’t know why people give it so many thumbs down. We did a city tour, visited the Lindt chocolate facility, a boat ride across the lake and enjoyed a couple of great dinners. No, it’s not the BO but not much can compare to those views unless you go to Zermatt which also frequently gets a thumbs down. Again, I don’t understand, yes the town is crowded and a bit cheesy but the hiking and views are incredible and our dinners were wonderful. I will be forever grateful to the woman in the Intersport store that adjusted my trekking poles free of charge.

Not knowing your date, I picked Sept 11. First I looked at www.bahn.de, then checked www.sbb.ch/en, which gave me the same results with a price of of 49 CHF for a Super Sparpreis Europa Ticket, which is train specific and nonrefundable and purchased today. Plus 5 CHF for a seat reservation on the Basel-Karlsruhe leg.

The Lauterbrunnen Valley needs five nights not two. You want to add a night when going into mountains. There is plenty to do so you won’t be bored.

Lucerne is charming, I'd keep it on the itinerary. Plus, it's an easy commute from the Zurich airport, so once you land, head straight to Lucerne. Also, mountain weather is very moody, and if you have clear skies, go out to Mt Rigi from Lucerne. If you have a morning with blue skies, go to a summit, don't waste a great day, because you don't know which of your days will bring cloudy weather.
Just my 2cents worth.
Have a great trip!

For 2 weeks, starting 6 SEP, the Wurstfest is running in Bad Durkheim. This is a huge winefest; biggest in the EU. Speyer is also having their Altstadt fest that weekend. If that's in your timeline I'd make an effort to attend. Both of these are an easy train ride from Heidelberg, but (as someone's already noted) there's a lot of construction on the lines around Mannheim and DB is using busses because the rail is down. That means anything headed to FRA through Mannheim you're going to be on a bus. This may change before you need to travel, but you'll need to check.

That being said, I'd aim at going back to Zurich, and then flying to Luxembourg. The trains from there can get you into FRA, it's a 2.5 hour flight, and you can spend some time on the Moselle or the Rhine. You might consider a route like this: Luxembourg, Saarbrucken, Trier, FRA.

Thank you all for the help!