Our Main Roads: The Real Difference Between Interstates and Highways

By Audrey W. | Arcadia Staff
With the many kinds of thoroughfares there are threading the country, it’s often hard to discern between types. The nation’s need for reliable roadways sparked a project that would forever change how Americans traveled by car. Highways and interstates form a grid that connects people across the United States. They make transportation accessible, efficient, and safe, but at the same time they share many of the same characteristics. Here’s how to tell the difference between interstates and highways on your next road trip.
From Highways to Interstates
The American highway system is the backbone of modern American transportation. For years, this was how people moved throughout the country. Highways took up little space, allowing for easy construction through towns and cities. Early highways were made from compacted dirt and were easily muddied by rain. While inner-city travel was made accessible for residents, the highways were bumpy and unpredictable. Throughout their use, highways have adopted a variety of names: scenic highways, routes, streets, and state roads, to name a few.
During the early years of American transportation, these highways were adequate. At the end of the 19th century, there was one motorized vehicle for every 18,000 Americans. But that all changed in 1908, when Henry Ford introduced the Model-T to the market at a price that was affordable for most Americans. The car was suddenly no longer a luxurious toy for the wealthy, but a practical tool for the nation’s middle class.
Ford halted its production of his “Tin Lizzie” in 1927, but not before selling nearly 15 million cars. With so many new vehicles on the road, the dirt-packed highway system that had served the public for decades needed an update. Uneven roads meant frequent accidents and there was no easy way to make a long distance trek.
Americans needed something their cars could gain traction on and wouldn’t get their wheels trapped in the mud. In June 1956, President Dwight Eisenhower signed the Federal-Aid Highway Act of 1956. This designated 41,000 miles of land for the “National System of Interstate Defense Highways.” Eisenhower declared these would eliminate inefficient highways and the inner-city traffic jams that plagued the nation’s current highway system. His administration planned to provide “speedy, safe transcontinental travel.”
While reasons to build the interstate system were abundant, funding was not. Building decent roads was expensive, and Americans questioned where funding for the project would originate. Advocates of the Act needed to convince the public and their elected officials that constructing the interstate highway system would benefit all Americans by being a public roadway. In most large cities, the main methods of transportation were streetcars, subways, and elevated trains, owned by private companies, and not the public. Car and tire manufacturers, gas station owners, and suburban developers pitched the new interstate as a project for the public.

A car driving down part of Kentucky’s Dixie Highway.

Their efforts were a success. Elected officials voted to use taxpayer money for the improvement of current highways and the construction of the transcontinental interstate. The Act allocated $26 billion to pay for the project, promising that the federal government would fund 90 percent of the expenses. The remaining 10 percent was funded by a 3-cent increase in gas prices that were funneled directly into the Highway Trust Fund.
When work on the interstates began, Americans were generally enthused. However, their opinions shifted when they witnessed the consequences of such an ambitious project. As new interstates sliced through communities, more and more people were displaced from their homes, and towns were cut in half. This led to the decay of several smaller cities and caused many people to wonder if building the interstates was worth the cost.
Despite these worries, the project continued as planned. Thirty-five years later, the interstates were complete. The final product was more than 46,000 miles long.
So what’s the real difference?
The American interstate system is longer, faster, and wider than the original highway system, but highways have still proven to be a crucial part of American transportation. Interstates have at least two lanes going both directions, on and off ramps, and can be identified by a blue shield. I-90 is the longest stretch of interstate highway, connecting Seattle, Washington, and Boston, Massachusetts.
Highways, on the other hand, usually have two to four lanes total, crossroads where traffic is forced to pause, stop lights, and require slower speeds. They take up less space, allowing them to route through towns and cities without disrupting the people who live there. Highways are marked by white signs with black lettering in the shape of a shield.
Today, both interstates and highways are used regularly by Americans. Where interstates allow people to travel long distances in relatively short time, highways weave through towns and cities and help to keep traffic orderly and efficient. Both are vital in the safe transportation of Americans on the road.