The closest major airport to Montgomery, Pennsylvania is Williamsport Regional Airport (IPT / KIPT). This airport is in Williamsport, Pennsylvania and is about 14 road miles from the center of Montgomery, PA.
The nearest major airport is Lancaster Airport (LNS / KLNS). This airport has domestic flights from Lancaster, Pennsylvania and is about 6 miles from the center of Manheim, PA.
The closest airport would be the Lancaster Airport in Lititz, it is a very small local airport, it carries one major airline, which is South West. The closest major airports, if that's what you want, would be the Philadelphia Airport (PHL) which is about 80 miles away, and the Baltimore Airport (BWI) which is around 90 miles away.
The nearest major airport is Erie International Airport(ERI / KERI). This airport has domestic flights and is about 6 miles from the center of Erie, PA.
The nearest major airport is Lancaster Airport (LNS / KLNS). This airport has domestic flights from Lancaster, Pennsylvania and is about 17 miles from the center of Quarryville, PA.
The closest airport is Trenton, NJ maybe 15 miles north on I-95, which has some scheduled serivce to other parts of the country. Try http://www.ifly.com/trenton-airport for mor information. The closest major airport is Philadelphia International Airport approximately 40 miles south on Interstate I-95. It is serviced by most major carriers.
The nearest major airport is Harrisburg International Airport (MDT / KMDT). This airport has international and domestic flights from Harrisburg, Pennsylvania and is about 19 driving miles from the center of Mechanicsburg, PA.
There is nowhere called "Leaviton" in Pennsylvania. The closest name to that is 'Levittown , Pa. The closest airport is Philadelphia International, about 50 Km southwest.
You could fly right into the state if you wanted to for example Philadelphia International Airport (PHI) or Pittsburgh International Airport (PIT). If you only want to get close without entering the state you could consider Newark Liberty International Airport (EWR).
The nearest major airport is Elmira/Corning Regional Airport (ELM / KELM). This airport has domestic flights from Elmira, New York and is about 42 road miles from the center of Mansfield, PA.
The largest airport may be Buffalo, NY at 78 miles away.
I would say it would be Cincinnati Ohio Airport.
Newark, NJ either downtown or at the airport. Both are on the Northeast Corridor.