boat to Ostia Antica

Not sure exactly what you are asking? Ostia Antica is the old port city for Rome on the Tiber. It is a national park still bordering the Tiber. General access to OA is via train from Rome. While there is a dock there I am unaware of any regular boat service to OA. And I am not sure where it would come from but it would have come for the south towards Lido di Ostia because the river is very silted in and only shallow boats could go on that part. Lido di Ostia is the beach town somewhat south of OA when many locals go for beach activities. If there is boat service it would have to be very local.

I have never heard of a boat ride to Ostia Antica. I only know of a train that goes from Rome to Ostia Antica and the beach nearby. Of course, I only did a day trip.