The downside of taking the night train from Rome to Venice is that you arrive very early, around 05:30. That's also an upside: you can admire Venice at dawn (the other advantage is not losing a day of vacation).
We rented a lovely apartment in Venice, right across from where Marco Polo lived long ago (which made for good educational opportunities with our sons :-). Fortunately the landlord was able to meet us early on a Sunday morning so we could drop off our bags, then it was off to Piazza San Marco, the principle square of Venice, to show the boys some of the beauty of the city.
One of the great things about Venice is that just going somewhere is an adventure given the novel boat-based public transportation system. Our sons enjoyed the trip down the Grand Canal, esp. lovely (and quiet!) in the early morning. We had fun trying to spot as many winged lions as possible, the symbols of Venice.
At the Piazza we admired the architecture, walked around, climbed the campanile (tall bell tower) to get a panoramic view of the city, and visited San Marco Cathedral's museum. All hits with young and not-quite-so-young :-)
- A travel pass is expensive but if if you're going to take a vaporetto (a "bus boat") more than twice a day, it's worth it. We paid 33 Euro for 3 days, the cost of a single ticket is 6.5 Euro
- Pay attention to tides (and this site) if you want to see Piazza San Marco partially flooded, the most you're likely to see, but be ready to stand on crowded walk ways
- The museum in San Marco's cathedral is well worth seeing for its view of the Piazza and its beautiful mosaics
- Time your visit to the campanile with the top of the hour and you'll be treated to nice bell ringing (loud too!)
- FYI, Sunday mornings the cathedral itself is close to tourists until 14:00 due to mass being held, though the museum is open
- It's easy to get a little disoriented in Venice's streets. A GPS or GPS enabled phone (or in our case, iPad) is easiest, a compass can be quite useful, but just paying attention to signs saying "Per Rialto" or "Per San Marco" can often be good enough when navigating the city. Besides, it can be fun to get lost!