U.S. Interstate Highway System

Interstate Highway
Interstate Highway

In 1919 shortly after the conclusion of World War I, the United States Army organized a convoy that departed Washington, D.C., bound for San Francisco, California. The objectives of the cross-country trek were to test military vehicles and ascertain the feasibility of mass transport on a nationwide scale.

The trip took 62 days. Twenty-five years later General Eisenhower commanded the invasion of Europe during World War II and noted the ease and freedom of movement for the troops.

Early attempts to construct a national highway system in the United States were woefully underfunded; President Franklin Delano Roosevelt had proposed such a project as a means of putting the unemployed to work during the Great Depression and World War II.


Elected president in 1952, Eisenhower advanced an agenda that led to the Federal-Aid Highway Act of 1954, under which state and federal governments would match road and bridge construction costs. Two years later, Eisenhower signed the Federal-Aid Highway Act of 1956, which provided federal funding of $25 billion for a highway system.

The roads were designed to accommodate traffic volumes expected 20 years later. Lanes were required to be 12 feet wide with a paved 10-foot shoulder; a minimum of two lanes in each direction had to carry cars at speeds of 50 to 70 miles per hour.

U.S. Interstate Highway System
U.S. Interstate Highway System

More than 41,000 miles of highway would be built. North-south roadways were designated with numbers ending in odd integers; east-west interstates were given even numbers. Alaska is the only state without an interstate highway.

Eisenhower may have considered a highway system necessary for the efficient movement of military equipment and personnel or the effective evacuation of cities in event of a nuclear attack, but the effects on the economy were much wider-reaching.

Suburbs grew, construction jobs were created, and commercial freight was transported; more automobiles were built, and roadside businesses developed. There were drawbacks as well, some becoming clear only later.

Highway traffic
Highway traffic

Many older cities embraced interstate projects only to find that downtown business districts could now be bypassed entirely. Interstate routes disrupted urban neighborhoods and slashed across farmers’ fields.

The ease of interstate travel discouraged mass transit and helped speed the demise of long-haul passenger rail service. Interstate maintenance and capacity issues continued to create friction between the federal and state governments.