Hi all,
1) Do trains have many stops during this journey?
Does it have many stops on the way? Can I get off at some locations and get back on to the next stop?

2) How does the fare work? Do I buy tickets from Frankfurt to Berlin and keep the ticket to get off and show the ticket to get back on? Do I need to pay extra fares bc I get off and back on?

3) What's the website for the best train fares? Is roundtrip saving me $$$ or same fares like 2-one way trips
4) Is the train sightseeing worth it? or I should just fly to Berlin.

Thanks

I can't answer all your questions, but can recommend https://www.seat61.com/ as a excellent source of information.

For me, I'd take a train rather than flight. Getting to a train station is usually easy, as train stations are generally in city centers, and you don't need to arrive much in advance of a train departure. Flights? Well, you generally need to get out of town (time!), be there 2+ hours in advance (BIG time sink), only to land somewhere that isn't nearly as central as a train station (another hour or more lost....) So whatever the actual transit time, a flight is likely to 4 or more hours more than a train. Costs are usually greater, too, because of the costs of getting to and from the airports. AND flying is not a very green option. So, as I said, train rather than flight for me!

I addition to the wonderful Man from Seat 61 website, you can consult rome2rio.com for transportation options -- and if you click through to the underlying sites (which you SHOULD do to get accurate info), you'll find lots of info about stops, prices, etc.

Hope that helps!

https://int.bahn.de/en will have some of the answers for you as well as the wonder Man in Seat 61.

Please don't fly, apart from it eating up a lot more time than you realise, it is very polluting.

Trains about every hr and a bit faster (door to door) than the plane.