Water Tours 

When touring the city of Philadelphia, we strongly recommend a water tour as a "path less taken" type of affair.  The Delaware River is blocks from the city's historic area and affords some great views.  The following organizations offer informative and interesting views of the area that you might not be able to see anywhere else.  Give them a shot; you won't be disappointed.

Liberty Belle Charters Incorporated
At Penn's Landing
337A North Front Street
(215)629-1131

Liberty Belle offers lunch, dinner, and even moonlight cruises in a steamship that dates back quite a ways, making for an authentic experience.  There's no better way to view the Ben Franklin Bridge and some of the other big sights than while relaxing on the deck of a ship off the coast of the Delaware.  Call for reservations and availability, as dates and times vary.

 

Spirit of Philadelphia 
The Great Plaza at Penn's Landing
(215)923-1419

The Spirit of Philadelphia, which operates out of their office on Christopher Columbus Boulevard (or Delaware Avenue, if you're a traditionalist) and Market Street,  offers beautiful cruises on the Delaware River.  Some of the highlighted options include buffet-style dining, fully-narrated descriptions of what you're seeing, and evening dancing if you're feeling groovy like that.  Call ahead to book reservations or to see when the boat leaves.  Highly recommended.