Do I need advance reservations for Capri-Naples ferry or Naples-Rome train

We once bought Naples-Rome on the spot because we didn't know how long we would stay at the Archaeological Museum -- took a regionale train which made many stops and took much longer. If you have specific times in mind, why not book ahead for reduced fares?

The ferry just show up. If you know the date and time of the Naples-Rome trip, buy the tickets on line:

https://www.trenitalia.com/tcom-en

or

https://www.italotreno.it/en

We bought the Capri-Naples ferry when we were on Capri. No problems and it was July.

We were just there in May....some of the ferry times did sell out on the same day.

I can't attest to the ferry but we prebooked our Naples-Rome train on our trip in May. I am almost 100% certain the train was not sold out. It was at 1600. If you know how long you will need in Naples you can pre-book. We stopped on the way back from Salerno just to get pizza and I allowed entirely to much time. I wish I would have waited and bought tickets at the station in Naples.