What is the train fare for 2nd class traveling from Berlin round trip to Dresden?
Depends on the date, and the time of day. You can get a special (sparpreis) 92 days out, but they can go fast. So, plan ahead. All your answers are at Bahn.de!!! Remember to make your reservations for the green vault as soon as you get your date firmed up.
You can only get those Sparpreis fares online from the German Rail (Bahn) website. They go on sale 92 days in advance and are limited in quantity. If there are any left, they must be purchased at least 3 days before travel. Right now, I can see fares as low as €19 one way for one person, €29 one way for two. That's €38 RT for the first person, €58 RT for two. For these fares, at least one train for the trip must be a train of the Bahn (ICE/IC/EC).