The cool thing about Philadelphia is that it has true neighborhoods with unique identities, unlike a lot of American cities. Each one of these neighborhoods has their own day/night scene.
Some good neighborhoods for nightlife are all of Center City (19102, 19103, 19106, 19107), Manayunk/Roxborough (19127, 19128), University City (19104), Fairmount/Art Museum (19130), Fishtown/Northern Liberties (19125, 19123), and Passyunk Square (19148).
I may have missed some spots (it is a big city), but these should be enough to get you started. If you need anything else, all of my contact information is below.
Timothy M. Garrity | REALTOR® & Consultant
U S Spaces, Inc. | #RS314897
215-829-8850 x267 - Office
267-879-2716 - Mobile