Venice is divided into six sestiere whose origin is as old as the city of Venice itself. As far as we know, they have always been there.
The Venetians relied mostly on rainwater for their water supply, because other sources were unaccessible or unacceptable
Garbage collection in Venice today is more efficient, but suffers nonetheless from some of the same problems as always.
Venice has an unusual system of house numbers. It is a fairly recent addition to Venice, and it has something to do with taxes.