Best Train Pass for 2 Month Trip

Passes do not include local transit, with a few specific exceptions, like S-Bahns in Munich (but not U-Bahns or trams or buses). The subject is, I won't say controversial, but some people like them and some people were very disappointed when the found out how much they don't cover. Just be aware that our esteemed Mr Steves is in the business of selling passes, so take his advice with a couple grains of salt.

Paris- Barcelona will require reservation fees, as will Rome-Naples/Salerno, Naples/Salerno-Venice, Venice-Munich. Those fees are already included when you buy tickets outright. It is not valid for the Circumvesuviana trains, if you are looking at those.

I assume you'll be flying from Barcelona to your first stop in Italy as well as to Istanbul (from Berlin?). I bet you can beat the rail pass price handily buy committing to specific dates and times and buying the train tickets soon (or once they become available). You'll need to do the math, though, to be sure. I'd use trainline.eu for the price research rather than dealing with all the individual railroad websites at this early stage.

Skyscanner.com is a good place to look for intra-European flights.

When I compared prices, I was amazed at how much cheaper it worked out for me, to buy point-to-point tickets instead.

Literally worked out over $1000 cheaper for me, for about a months worth of travel. So I’d definitely recommend at least comparing the prices before you book a pass.

Kriega,

A Rail pass is generally not a good value in Italy, as P-P tickets are relatively cheap there. Note that passes do not include the compulsory seat reservations for the express trains such as the Freccia high speed or Intercity. You'll have to buy those separately out-of-pocket. Don't be caught without a valid reservation for the train you're riding on or you'll risk hefty fines which will be collected on the spot. Also note that Rail passes are not accepted by all rail networks in Italy. I don't believe Italo Treno accepts passes yet.

You'll also have to buy separate reservations for the high speed TGV trains in France. Those can be hard to get in some cases as passholder reservations are limited. Once the quota for a particular train is sold out, you'd be out of luck even if there were still seats available. If that happened you'd have to either buy a ticket or wait for another train which did still have passholder reservations available.

You might find this website helpful - https://www.seat61.com/Railpass-and-Eurail-pass-guide.htm

As others have said, the Eurorail passes are really not a good value, especially considering your journeys in France and Italy.

You might want to look into a German Rail Pass for that portion of the trip, the twin pass can be a good deal if you want flexibility on high speed journeys covering long distances. Otherwise, buying point to point tickets will save you money and the hassle of having a Eurail pass in France. If you buy in advance, you can get cheaper fares, although they lock you into specific trains, if you're on a budget it's probably worth it.

Also don't discount the idea of flying between places. Sometimes flights will be cheaper than train tickets.

Bologna, Venice, Munich, Gengenbach, Frankfurt, Berlin

These destinations are covered by a German Rail pass - Bologna and Venice only on the DB / OEBB Eurocity trains, however, so make sure that those trains are scheduled according to your needs. A 5-day twin flexi-pass is €168 each (€335 total) at DB.

I suggest you investigate this itinerary and strategy...

Fly into Paris, P2P tickets to Bayeux and back. Then...

(Flight - or P2P 8 hrs.) Paris - Berlin
(GRP) Berlin - Frankfurt
(GRP) Frankfurt - Gengenbach
(GRP) Gengenbach - Munich
(GRP) Munich - Bologna
(GRP) Bologna - Venice

P2P for other Italian destinations

Flights to Barcelona and Istanbul

(The unresolved French rail strike may or may not make for undependable plans to travel across the country to Barcelona, Italy, or Berlin. I would look into flights from there to Berlin or other places right away.)

Local metro is mostly not covered by passes or train tickets, so you can leave it out of the equation. In planning your route, also consider any small towns in between (that might or might not fall on separate rail travel days) and flights that could save some time.

For trains in France, Italy, Austria, and Germany, a Select pass to cover your 10 longest travel days costs about $500 per person (under ager 28), plus seat reservation fees (for most trains except in Germany). You would probably not choose a more expensive Global pass.

As already described, the benefit of the German Rail Pass to cover you northbound from Bologna or Venice on a direct, German-operated train is pretty nice.