Few people truly recognize the influence of modern transportation on society. In the United States, that includes the influence of highways that allow the citizenry to travel freely, the strength of the economy, and the country's national security. In all cases, the geography of the United States influenced the evolution of transportation and transportation technology. The U.S. is the third largest country in the world and includes a vast area of land (Central Intelligence Agency, 2012a). In 2008, the U.S. had the most kilometers of roads in the world--6,506,204 km--almost twice as many as China with the second most (Central Intelligence Agency, 2012b). The U.S. continues to construct highways because they are vital to the country's national security and economic growth. What are the costs of building, upgrading, and maintaining America's highways? What are the costs of not building and maintaining highways? How does the U.S. highway system compare to the highway systems of other countries? Why has the U.S. highway system evolved the way that it has? These questions are discussed in this article. A classroom activity about highway construction is also offered. (Contains 5 figures.)