Philadelphia International Airport (PHL) is the main gateway, with direct flights from most major US cities and several European destinations. The airport is 7 miles southwest of Center City. SEPTA's Airport Line runs trains every 30 minutes into the city, stopping at several Center City stations. Taxis and ride-shares to downtown take 20-30 minutes depending on traffic.
Amtrak's 30th Street Station is one of the busiest rail hubs on the East Coast. The Northeast Regional and Acela Express connect Philadelphia to New York (1.5 hours), Washington DC (2 hours), and Boston (5.5 hours). The Pennsylvanian runs daily to Pittsburgh and Harrisburg.
By bus, Greyhound and Trailways operate from the bus terminal at 1001 Filbert Street. Budget carriers like FlixBus and OurBus offer cheap fares to New York, Washington DC, and Baltimore.
By car, Interstate 95 runs north-south along the Delaware River, and I-76 (the Schuylkill Expressway) connects to the Pennsylvania Turnpike heading west. Driving in Center City is not recommended -- parking is scarce and expensive, and most attractions are walkable or reachable by public transit.