I went to Freiburg im Breisgau for work (it is in the very south of Germany). Really I could advice you that because Freiburg really is a very nice city. It is a real student city.
However, I went there by train. My train left from Utrecht.. And that was a nightmare.. (okay, now I am exaggerating a bit, I know) Anyhow, I supposed to travel from Utrecht to Frankfurt and change there on the train to Freiburg. But things went a bit different as a Train heading for Amsterdam was defective. So the Deutsche Bahn decided to stop our train at Dusseldorf and let it return to Amsterdam. So there I was in Dusseldorf.
Luckily I could take another route which went via Mannheim. So I was still on time in Freiburg.
You can see the pictures at http://marinheideman.nl