I am travelling to Venice 13th-16th May and have booked into the Hilton Stucky. The problem is that the return flight leaves at around 9am and I need to get from the hotel very early. Any advice greatly appreciated!
ATVO run excellent and reliable direct airport buses from Venice's Piazzale Roma to Treviso airport. Timetable:
Info and online booking in English:
You will need to catch the 0530 bus in order to get to the airport in time for your flight.
The hotel has its own shuttle but its timetable will not work for you:
The hotel can book a private water taxi for you (not cheap, I'm afraid). Unfortunately, the public vaporetto (water-bus) Line 2 from Giudecca to Piazzale Roma will not work if you want to take the ATVO airport bus. Line 2 timetable:
Unless you can manage to stay overnight on Venice's main island I think you will need to organise a water-taxi from the Hilton to Piazzale Roma in order to catch the 0530 ATVO bus to the airport.
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I would imagine you have time to change your reservation without penalty. I would change the last night to a hotel closer to the airport. Spend the day in Venice then get your transport out to the airport in the late afternoon.