Although Naples doesn't have the nightlife heft of the heavyweights on the international scene, there are pockets of activity in various parts of the city that will provide the type of experience you'll be looking for, whether its a casual drink as the sun goes down, a chance to feel bass rattle your molars or anything in between.
One of the first nightlife options you may encounter, depending on your mode of transportation, is the highly accessible Piazza Nacionale just north of the Naples Central Train Station. The complex itself is home to a number of (overpriced) cafes, while the area around the plaza has a few quality cafes/bars. There is a good late night buzz in Centro Storico (the old town), particularly from Piazza San Domenico Maggiore to Piazza Dante Alighieri, while the lovely Vomero neighborhood may have the highest concentration of bars and lounges in the city, starting at Piazza Medaglie d'Oro up the hill to Piazza Luigi Vanvitelli. Following Via Aniello Falcone (which has a few cocktails with stellar ocean views) south to Chiaia's waterfront, you'll get a great diversity of entertainment approximate to the refreshing greenery of Villa Comunale. Lastly, a trip to the outskirts of the city to the commune of Pozzuoli may be in the cards if you want to join the locals who head to the "Lugomare" (the waterfront) on the weekends. There are a few bars/cafes that get busy in the area that don't usually see a lot of tourists.
For further information, browse our included neighborhoods or pose a question to the embark community in the comments section.Chiaia- riverfront Centro Storico- Vomero- Naples Central Station and Piazza Garibaldi