I was curious about your claim that Philly is within the top 5 largest cities in the US.

Philadelphia is the economic and cultural center of the Delaware Valley, home to 6 million people and the country's fifth-largest metropolitan area.
Houston is the seat of Harris County and the economic center of Houston–Sugar Land–Baytown, the fifth-largest metropolitan area in the U.S. with over 6 million people.[6]
oh, wikipedia...