Although I have been to Venice about 15 times, last week was the first time I used Alilaguna. Since it was December and there are few tourists, it was not crowded. Here are the pros and cons
If it is not high season it is much nicer to arrive in Venice by boat than on the ACTV express bus that goes by the awful industrial site of Marghera en route to Piazzale Roma.
If your hotel is directly at one of the stops (mine was this time) in Venice, it can mean not having to carry luggage over bridges
It is over double the price (@ 27euros RT) of the express bus (11), though you'd probably have to buy a vaporetto ticket a P.le Roma anyway
It takes much longer -- an hour -- and only runs twice an hour
You have a much longer walk (5-10 minutes) to the boat stop/airport than with the bus, which is right across from the entrance
In the future, I'll stick with the bus.
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