I've never made it to South Philly's Italian area. Any recommendations for authentic Italian dining there? Also wanted to ask the same about Old City and Rittenhouse Square areas. Need to make a reservation asap for next Saturday.  Thanks in advance!

In South Philly, Ralphs on 9th street is a local, old world fave serving authentic Italian delicacies for over a century. Old school, cozy with an upbeat vibe.  
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In Rittenhouse, Rouge provides new American cuisine with a very hip and lively bar scene. Parc serves excellent French fare but if you are in the mood for steak and seafood, try Devon. All 3 are located in the same block roughly and is my favorite area in the city to people watch as alfresco dining is available at the first two.

Do you have any suggestions for Italian restaurant in the Rittenhouse/Center City area?

It's only 5 minute walk from Rittenhouse and it's fabulous. It's more chic & trendy, and not old world Italian, but the food and ambiance is off the charts good. The space and decor is more modern and atypical for Italian, but that also gives it a unique dining feel and experience.

Used to be a great little bistro a block off Rittenhouse in the Arts Alliance building which is an old mansion. Think it is now going as Amourette

I am a lover of authentic food, so here is the soft whisper that is coming soon.....