Travel in France, Switzerland and Italy.

I'd say "not necessarily". Rail passes usually don't save money these days. Your trip is a bit unusual in that you're going to three countries but the Swiss Travel legs are probably going to be a really substantial part of your rail costs. Swiss rail fares are very high, per mile--so high that some sort of country-specific pass might be best for you, in combination with early purchase of point-to-point tickets in France and Italy purchased once your itinerary is locked down.

Can you tell us more about your travel plans in Switzerland? Are you taking high-mountain transportation up from Lauterbrunnen, for example? That might affect recommendations since Switzerland has several pass/card options.

Thanks, Our travels in Switzerland are simple. Chamonix to Interlaken, Interlaken to Lugano. We are now looking at a 5 day Within one month Euro Global pass.

do you know that Eurail passes are not valid beyond Interlaken Ost? Or at least the big sign there used to say that. So for Lauterbrunnen and everything beyond that you will need a ticket (actually from Interlaken).

Nigel I too saw that sign a few years back, big as day. Obviously they had a lot of pass "issues" and took the initiative.

For train pass matters, the best place to do research is Man in Seat 61. It can get kinda complicated (and your autocorrect turned Eurail into Aural). If need be, you can use Rick's suggestion of Raileurope and lean on their advice which you will end up paying for.

When I use the Eurail trip planner for all of my planned destinations there is no comment about the pass not being valid between Interlaken and Lugano. How can I verify this?

We weren't talking about Interlaken to Lugano were we? It is valid from Interlaken to Lugano, either via Spiez or Luzern .

I was talking about beyond Interlaken up the hill to Lauterbrunnen and beyond.

OK Thanks. We were talking about two different things. I feel much better now.

The train part past Interlaken is on the Berner Oberland Express (BOB) cute little red trains which a normal rail pass will not cover. There are multi day passes for the BOB and part way up the mountians on both sides of the Lauterbrunnen Valley, past Brig on one side and if I remember pass where the clog wheel starts on the otherside need to be purchased seperatly. J

The trains and lifts up the valley or the mountain from Interlaken to Lauterbrunnen, Schilthorn, and Junfraujoch are discounted 25% with a Eurail pass. No need to use one of your counted travel days to get these discounts.

Eurail Passes are now on sale for 10% off if purchased by March 21. Your trip will likely require just a couple of paid seat reservations in addition to the pass - departing Paris and then later between Milan and Venice.