Don't drive into the city for July 4th festivities and then be surprised that you and the other couple of hundreds of thousands of people are competing for parking.
Pro tip: if you must drive into the city, park west of Broad and south of Washington and then take the subway to where you want to go.
Trains running late for the 4th. Subways running all night. With subways running all night, the Norristown High Speed Line is probably your last best hope to getting to the western suburbs. Last one leaves 69th st. at 1:42. Miss that one and the first one leaves at 4:20.