I can see why you have concern.

Some year ago we were able to get to Sweden and Denmark when a colleague backed out of a free trip there due to travel concerns -- so glad we went and enjoyed the trip.

I was on the Tube in London the day after the 7/11 bombings. While it was sparsely populated, and my carry on bag did catch a few glances, it went fine and due to jammed traffic was the best way to get where I had to go. Other than announcements (that the train would stop before it got to Edgeware Road etc.), it was definitely keep calm and carry on.

All that said -- in your shoes I would go to Urbino. University students, out of the way, wonderful history, in Italy--actually I am finally getting there next September after many attempts. Much as I loved seeing Barcelona, loved the vibe, appreciated the art, I think you want to look forward to your time abroad, and you may have less concern going to Urbino.