While I tend to like to travel to more rural destinations, Vienna is a fantastic city. I had the ISSRM conference there last summer where I presented research on Medical Tourism (topic for a lecture on 22 April 2010).
The photo was shot on one of my walks around the downtown area and is the Staatsoper Opera House. I didn't get a chance to see an opera, but did observe waltzing lessons and had a dinner in a Palace one night. Our hosts put on a great spread. Oh yeah, the paper went well too.
I'd highly recommend Vienna for a trip.