Berlin is a very cool city, as good a place to visit as any in Europe imo. And the weather is superb in summer too, that's not really an argument.
Sure if when you think "Germany" what comes to mind is Stuttgart, Essen, Hannover, etc. it kind of sucks, but Berlin is on a whole different level.
Well, I have been to both places. And I'm not saying Berlin is a
bad place. I'm just saying that as a vacation destination, Barcelona is way
better. Beautiful beaches, breathtaking vistas, Gaudi architecture all over town (it's more than worth it going to Barcelona, just for that alone!), a beautiful Gothic quarter, museums, fabulous Spanish food (and yes, I realize you can get ethnic food in Berlin, but that's sort of not the point, since you can also get all manner of ethnic food without even leaving the USA.

It's really not the same as eating the food in-country - and that goes for ANYWHERE you go on earth), wonderful day trips from the city, even a very cool aquarium! In Barcelona, just walking around is an experience - La Rambla is, as the name indicates, a wonderful stroll, and Parc Guell (designed by Gaudi) might well be my favorite park on earth, combining one-of-a-kind architecture and layout with a breathtaking view of the Mediterranean. And the outdoor nightlife in Barcelona is magnificent - relaxed, casual, and as is typical of Mediterranean Europe, tons of relaxed no-pressure fun.
And are you seriously going to tell me that the weather in Germany is as good as the weather on the Spanish coast of the Mediterranean Sea?

I mean, I see a lot more German tourists in Barcelona than the reverse.
I don't know....for my money, I'd pick Barcelona every time, given a choice between the two. If you can do both, by all means do both. But if it's an either/or proposition....
In truth, for my money, as a vacation destination, I'd choose your own city of Vienna over Berlin, to be honest. And Austria as a whole over Germany as a whole. But what do I know?
