The use of cars and trucks over the past century has remade American geography-pushing big cities ever outward toward suburbanization, spurring the growth of some small towns while hastening the decline of others, and spawning a new kind of commercial landscape marked by gas stations, drive-in restaurants, motels, tourist attractions, and countless other retail entities that express our national love affair with the open road. By its very nature, this landscape is ever changing, indeed ephemeral. What is new quickly becomes old and is soon forgotten.