Island cities where the streets tend to be very wet. Saint Mark's in Venice was built in the 800s, a Byzantine style structure that has to be seen to be believed. The new stuff in town is 800 years old. We stayed in a hotel that was established in 1290 (yes, they had updated the beds and plumbing).

Murano is a major glassmaking center. The activities were moved there from Venice in the 13th century to reduce the risk of fire in Venice. There is still active glassmaking there, you can tour a factory.

(August 2007, December 20 - added/replaced a few shots with negative scans)