Subway from Genoa to Genoa (city)
Genoa has a small but efficient underground network with only 6 stations. They are all on the same line. Opposite the cruise terminal is the Principe metro station. Here you can take a subway to Piazza Caricamento (Darsena) at the Old Port or to Piazza de Ferrari in the historic center of the city. A ticket costs € 1.5 per person (one way, valid for 100 minutes after validation).
To get to the Principe metro station take the stairs up at the cruise terminal. From the small square with the fountain in front of the terminal cross the bridge. Cross the busy road and follow the V. Fanti d'Italia. In a few minutes you are there.