Translation:I will send you to Europe after college.
Because "nach der Hochschule" doesn't mean "to college". In Standard German, "nach" in the sense of "to" is almost exclusively used with cities/countries/continents (e.g. "nach Deutschland"), not with other places. Therefore, "nach der Hochschule" means "after college". "Nach Europa" can theoretically both mean "after [I send you to] Europe" or "to Europe", but "I will send you after Europe after college" would be nonsensical.
That sounds good :). If it makes you feel any better, I'm surrounded by native German speakers who use nach in the "wrong" places all the time. I sometimes do that, too. My grandmother almost always used "nach" when talking about directions of any kind. She also mixed up the dative and accusative cases a lot. That was of course because in her dialect, "nach" ("noh") is indeed the correct preposition and there is just one form for both dative and accusative.
From my experience, people just compare the dialects themselves when moving between different states, mostly vocabs and pronounciation. The small differences among villages fade, in my opinion, since younger people aren't as involved with one specific local dialect like their grandparents, for example, who grew up with very distinct dialects. That's just my experience with swabian and might itself be a local occurance though.
I think it's generally like that in the U.S., with the exception of a few relatively isolated pockets and also Amish communities (which speak a Germanic dialect but also English).
Sometimes accents are quite different, or manner of speaking. I lived for awhile in another mountainous area that, until recently, had been very poor and isolated. It was months before I understood anything that the locals said to me. I doubt they understood me, either. I also had to learn to speak much more slowly: if I forgot and spoke at my usual rate, I think I frightened people!
Television changes all that, though: and as you say, younger people are more involved with a national culture than older people are.