Train from Venice to Vernazza (CT)

You are correct that the trenitalia site is confusing when you try to buy your tickets ahead of time here in the US.

Suggest you wait and buy your tickets upon arrival in Venice a day or two ahead. The ticket office staff speak English or you can use the automated machines. Last year, I took a train which left Venice about 8:45 a.m going through Florence, La Spezia and then the milk train to Vernazza.

Also, be sure to allow plenty of time to get to the train station from your hotel if using the public water transport. From a San Marco area hotel, allow 1-1/2 hours.

"You are correct that the Trenitalia site is confusing when you try to buy your tickets ahead of time here in the US."

Okay, let's go over this one more time:

The Trenitalia site does not accept US credit cards, period.

It's not just confusing--your US credit card won't be accepted, no matter what you do.

For anyone who wants nuanced exegeses of this frustrating fact, there are dozens/hundreds of posts on this forum on this subject, which can be found via a search of the site.

But the above is all you really need to know.

You cannot go directly from Venice to Vernazza. The routes vary depending upon the time of departure.

You may find the timetables on the German Rail site to be easier to handle. After you get summary timetables for Venezia Santa Lucia-Vernazza, click on the arrow to the left of each departure time to see the connecting points.

Some runs from Venice to Vernazza go via Milan/Genoa. Many others go via Florence/Pisa/La Spezia. The travel times are about the same so it doesn't make much difference.