Road Trip advice. Starting in Frankfurt, thinking of heading towards Austrian Alps. I have ~1 week.

I'm going to be getting to frankfurt may 12 and fly out from there may 20. I love old castles and mountain hiking during the day and techno and good beer in the evenings. not married to the Austria destination, have spent a lot of time in Swiss Alps, thinking of mixing it up in the eastern alps. Thanks in advance for any and all advice!