Lists of American airports, divided by state. Every state with four or more major airports has been included. If you travel domestically within the United States, then you've probably been to at least a few of these airports. Air travel is a gift of the modern age. Airplanes are an amazing invention, despite all of the hassle. As air transportation has become more popular even some of the smaller states have multiple international airports. The list includes some of the top biggest, largest, and busiest American airports.