Most boat and ferry services leave and arrive from Molo Beverello, just below Piazza Municipio and the Castel Nuovo. SNAV and Alilauro run a hydrofoil and fast ferry service is also based at Mergellina (a short walk from the train station of the same name), and ferries to and from Ischia and Procida run from the port at Pozzuoli.
Medmar, Caremar, and Navigazione Libera del Golfo send boats to the islands all day until 7 or 8, though in the off-season service is less frequent. Prices vary wildly depending on time of year, carrier, and type of boat (the quicker hyrodfoils often being notably more expensive). Major destinations from both ports include Capri (hydrofoils: 40 minutes south; ferries: 1 hour 20 minutes), Procida (hydrofoils: 30 minutes southwest; ferries: 1 hour), and Ischia (hydrofoils: 40 minutes southwest; ferries: 1 hour 20 minutes). Several hydrofoils also ply to Sorrento (25 minutes southeast).
If you're heading to the Aeolian Islands, other parts of Sicily, or Sardinia, Naples may be a convenient departure point. A major long-distance carrier is Tirennia, which departs from Stazione Marittima, near Piazza Municipio. Tirennia's main competitor is Linee Lauro, which departs from Molo Belvedere below Castel Nuovo.
The Metro del Mare is a hydrofoil service designed like a bus route, and five lines connect Pozzuoli to Naples and go on to Sorrento, the Amalfi Coast, and the Cilento region farther south during the summer months. Tickets can be bought at the ports themselves, though there are often long queues during weekends in summer, so try to book in advance, especially if you're taking a car with you.
Departure times and additional info on some routes, including the local ferry and hydrofoil lines listed below, can be found in the newspapers Il Mattino, La Repubblica, and Corriere della Sera.
Alilauro (081/7614909. www.alilauro.it). Caremar (081/5513882. www.caremar.it). Medmarnavi (081/5513352. www.medmargroup.it). Metro del Mare (199/446664. www.metrodelmare.com). Navigazione Libera del Golfo (081/5527209. www.navlib.it). SNAV (081/7612348. www.snav.it). Tirennia (081/7201111. www.tirrenia.it).