'Be Italian Flat Duomo 319' is a hotel close to the Porta di Massa Port. It's perfectly located if you plan to explore some of the nearby islands and have an early ferry.

I stayed here last summer, as I wanted to have a day trip to Procida and it was really convenient both for the location and the quality of the room.

I'd highly recommend if you need to stay close to the port, or need a room in a central area of Naples. It's close to the underground and you can reach most areas pretty easily by just walking.