Venice is a pedestrian city and the only way to get around is on foot or on water transport along the canals. That is why transport is so expensive: private water taxis cost 60€ for short trips (around 130€ for every 30 minutes) and the vaporettos (water buses) cost 9.5€ for each ticket, which can be used for 1h15min.
Unless you are a large group of 10 or more people (in which case it makes sense to take a private taxi), you should buy a pass for the vaporetto network (ACTV), which entitles you to use these water buses as many times as you want to get to the city´s most interesting sights and are valid for a certain amount of time. These pases can be bought from the ticket offices of ACTV - Venezia Unica (at the train station, in the Piazzale Roma, at the airport or in vending machines at some vaporetto stops) or online.
- 24hrs ticket = 25€
- 48hrs ticket = 35€ (recommended for this Smart Route)
- 72hrs ticket = 45€
- 7 days ticket = 65€
If you are under 30 the most economical thing to do is buy a "Rolling Venice Pack" once you have arrived in the city. It costs 33€ and includes 3 days of transport, 24h of free wifi and some discounts for different city attractions.
Downlaod PDF official map of Vaporettos: