Squeezed by the Potomac River on one side and Arlington County on the other, National has endured for six decades as a destination airport: Fly in, fly home. Now, with no room for growth, it is growing nonetheless, becoming a mini-hub airport for an airline industry that has been transformed into a transcontinental network of hubs.

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Growth is great unless passengers get so turned off from long waits that they stop coming all together. Photo by Elvert Barnes.

The new role as transit point has meant larger planes, more passengers and tons of additional luggage. Added to that, its most regular passengers — members of Congress — have insisted on new flights to the more distant cities that some of them call home.