security

I'd expect it to be only slightly more prevalent than it was when I was there in September. There's an ongoing risk of terrorism, so there's always a police presence in public places such as rail stations. I also noticed Army personnel in Piazza San Marco.

Diane, as Ken said you may notice more security presence (no idea when your trip is) but heightened security at major tourist attractions throughout Italy has been in place for some time. Procedures can change at any time depending on the current climate/ specific threats so just roll with whatever is required.

We just left Venice yesterday. The atmosphere was typical of what it has been on all of our many trips there: no one seemed overly worried, although obviously we are all saddened by the events in Brussels.

Police presence around San Marco and the train station was the most obvious. At the Basilica the line was moving fast, though.