Padova to Venice Cruise Port

If you bring up a map of the Venice cruise port you will see the train station close by with parking and a people move in the proximate location. The bus to the airport is in the similar area. I suspect the other buses are too. I don't think it makes a whole lot of difference.

The bus will take you to Piazzale Roma, most likely . From there take the people mover to the cruise port. If it were me I would take the train. Your walk to Piazzale Roma will be about 300-400 yards from the train station (Venezia Santa Lucia). Then the same as the bus, take the people mover. I would take the train because it will be a bit faster, and baggage could be less of an issue. Plus trains are cool.

If you arrive at Ferrovia, the train station, and want to get to P.Roma to connect with the People Mover you have to cross the Grand Canal. Great views. Either the glass bridge up and over, or one €7.50 stop on the vaporetto (bus boat).

Bus from Padova to P.Roma will be more convenient, train and crossing the Grand Canal will be much more scenic.

Easiest way. Train to Mestre and land taxi. Taxi can take you to your ship.

It sounds to me that you don't want to go to the cruise terminal, but to somewhere in Venice FROM the cruise terminal?
(Are there even any cruises going anywhere these days??)
Where exactly do you want to go in Venice?

Good catch, S J, I didn't register the question's detail

Sorry not being clear. We hope to take a cruise out of Venice in June 2021. We will be in Padova the night before. In the morning we want to take the train or bus to the cruise port which is in Venice. Of course this seems like a wild dream that the chance of travel would be possible..we do have till Feb to get 100% refund

It is easy enough to get from Ferrovia to P. Roma, across the Calatrava bridge. Easy enough to get the people mover from P. Roma to the cruise port (although if your ship departs from San Basilio, you will be walking about a kilometre from people mover to San Basilio). The cruise port is enormous, has capacity for eight liners, so you might be walking a lot with luggage.

A land taxi from Mestre station to the cruise port will take you close to your ship.

You are one year in advance, so things could change, but is not sure the ships can really stop in Venezia harbor. Is very easy the port will be Ravenna. Several groups just decided for 2021 to land in Ravenna.
Is not a matter related by the virus, but due to the pollution and damages that those very big ships can do to Venice's monuments.

Ricky, Guess we'll find out about the port, so far they say Venice. That will make changes in where we stay.

yes, there has been a long campaign to remove large cruise ships from the lagoon.

Given all the other changes recently you may very well find that your boat will park elsewhere for Venice.