I'm running some scenarios to see which sort of rail passes I might need for a trip May/June 2022. I am flying into Zurich for a few Swiss days to get rid of jetlag before heading to Venice to start Rick's VFR tour, following that with a Rhone-Saone river cruise before flying home from Paris.
I think a 4 day Swiss pass will get me from Zurich through Interlaken to Wengen for a couple of days, take the sting out of some lifts, get me back to Luzern for a day before heading over the Alps to Italy on the 4th day. However, I'm confused about the Luzern through Milan to Venice stretch. The Swiss pass will cover me to Chiasso but how and when do I ticket from Chiasso to Milan or Padova or Venice (depending on where I decide to end for the day) where the Italian train appears to require a seat reservation but the Swiss leg does not? How do I estimate what that cost is to determine If a Eurail Pass would be a good idea as I add in my French rail travel? (After ending the tour in Rome I'm flying to either Lyon or Marseilles and taking a train to Arles for a river cruise then train a final train stretch to Paris to fly home).
I HATE leaving things to chance (which is why no reservations on Swiss trains is freaking me out) and I have this obsessive-compulsive desire to run these scenarios. Really, the only pressing purchase is the Swiss pass while it's on sale. Also a Eurail pass has a cancellation benefit if purchased in the next few days.
So, long story short.... How do I cross the Swiss/Italian border if using a Swiss Pass?
Many thanks in advance!!!