Which would be a better Labor Day weekend trip, Louisville KY or Philly?

It really depends on what you're into. I like both cities, and have been to both several times. I would probably choose Philadelphia over Louisville because I think it offers a little more. There are a lot of historical sites, museums, and shopping areas in Philly. Great restaurants too - definitely get a cheese steak.

Louisville has the Louisville Slugger museum, great riverboat tours, and some other interesting sites, but there's not as easily something for everyone there as there is in Philly.

Houston could use the help.

Phila

Lots of crime in Philly. I don't know anything about Louisville; sorry.