Food
A must do....... The Reading Terminal Market FREE Until you want to buy food
Cool City Views FREE
Run up the Rocky Steps at the Art Museum, jump up and down with your fits in the air, and enjoy the view. Then catch your breath, you are at the back of the art museum. Walk to the other side, and look out from the front, you are looking out over the Schuylkill River and Boat House Row.
Also, check out this list of great Top Ten Views.
Weird and Sometimes Makes you Queasy
Just Weird Eastern State Penitentiary
Also Weird and wonderful Philly Magic Gardens (This has nothing to do with my tour, it is a magnificent art installation). If you like this work, here is a map to all sorts of FREE installations nearby
Your Cable Bill Dollars at Work
FREE - Watch a short movie inside The Sphere of the Comcast Center and at the Comcast Experience
Science Lovers - Walk through a gigantic heart! The Franklin Institute (great for kids of all ages)