In 1919 a young army officer named Dwight Eisenhower took a long road trip across America with his fellow troops. Because the highways were in such bad shape, the trip (which was officially called a “convoy”) took 56 days and averaged less than 6 miles per hour. That’s really slow.

Many years later, when Dwight Eisenhower was elected president, he remembered that slow-poke trip across America. So he proposed a whole new system of roads that would allow cars,trucks, and military vehicles to go from place to place without having to stop for traffic lights, stop signs, or crosswalks.

Today, we take the Interstate Highway System for granted. But think, for a moment, about how bad traffic would be if the Interstate highways didn’t exist. So we all owe President Eisenhower a big “thank you” because he knew that good roads would be good for America. And he was right.

About the Interstate Highway System

It’s a Fact: Most of us call it “The Interstate,” but its official name is: “The Dwight D. Eisenhower National System of Interstate and Defense Highways.”

It’s a Fact: During World War II, Dwight Eisenhower was a high-ranking general in the United States Army. So, when he became president, he was concerned with national defense. Eisenhower viewed the Interstate highway system as, first and foremost, a way of moving troops and equipment. The fact that cars and trucks could use it was an added benefit. But, for Eisenhower, national defense was the most important feature of the Interstate highways.

It’s a Fact: Currently, the Interstate Highway System has 48,191 miles of roads.

It’s a Fact: Construction on the Interstate Highway began in 1956. It took 35 years to complete.

More Fun Facts About the Interstate

Fun Fact: When they began construction, it was estimated that the Interstate would cost $12 billion dollars. The system ended up costing $114 billion, which is less than $500 billion in today’s dollars.

Fun Fact: To put the total cost of the Interstate system in perspective, $500 billion is about half what Americans spends each year on the military; it’s also about half of what the government spends on healthcare (Medicare and Medicaid) and about half the amount paid out by Social Security .

Fun Fact: The highest point on an Interstate highway is 11,158 feet on I-70 at the Eisenhower Tunnel in the Rocky Mountains.

Fun Fact: The lowest point on an Interstate highway is on I-95, which goes 103 feet below sea level inside the Fort McHenry Tunnel (under the Baltimore Inner Harbor).

Fun Fact: Odd-numbered Interstates go north-south and even-numbered interstates go east-west. For example, I-65 runs north-south while I-40 goes from east to west.