Traveling to Abilene

Interstate Highway System


The Interstate Highway System

" Together, the united forces of our communication and transportation systems are dynamic elements in the very name we bear -- United States. Without them, we would be a mere alliance of many separate parts." -- President Dwight D. Eisenhower, February 22, 1955

An inter-state highway system was first considered in the 1930's. President Roosevelt expressed interest in the idea as a way of providing jobs. The Federal-Aid Highway Act of 1938 directed the chief of the Bureau of Public Roads (precursor to today's Federal Highway Administration) to study the feasibility of a six-route national toll road network. The study did not recommend a national toll road system since the then-existing traffic levels would not support its cost. It further recommended a 26,000-mile non-toll "inter-regional" highway network. In high-traffic areas, it would have two lanes in the same direction and limited- access design. The recommendation essentially asked for a 1930's version of today's Interstate system.

The Federal-Aid Highway Act of 1944 created a 40,000-mile "National System of Interstate Highways," but without national importance and no increase in federal funding. Construction of this system began in August 1947, but without increased federal support, many states balked at the idea. Road design standards were not always uniformly applied.

The Federal-Aid Highway Act of 1952 authorized funds on a 50/50 state/federal matching level. These were the first funds dedicated to this cause. But even then, the amount ($25 million) was not enough. When President Eisenhower assumed office in 1953, only 6,000 miles had been completed at a cost of $955 million.

Remembering his 1919 Army trip plus his reaction to how quickly German (and later, Allied) troops could move around that country in World War 2 on the autobahns (built in 1935), Eisenhower pressed for a national highway system. While he wanted such a system, he didn't start it as is commonly believed. What made the idea catch on was his ability to convince people that this was a national, not state, issue. After his transcontinental Army trip he thought a national network of two-lane, paved roads would be sufficient, and in the 1930's that was probably true. That changed after he saw the speed and efficiency offered by the four-lane German autobahns.

The Federal-Aid Highway Act of 1956, created today's Interstate system and was signed by President Eisenhower on June 29, 1956 in a hospital room without any fanfare. (He was recovering from illness.) The federal government would pay 90% of the cost, because it was realized now that this project was national in scope. It further called for road design standards to accommodate traffic levels forecast for 1975, which was later modified to a 20-year forecast. In 1966, all Interstates were required to be at least four lanes with no at-grade railroad crossings. Existing toll roads could continue as Interstate toll roads provided they met Interstate standards. In 1991, the U.S. Congress finally decided to repay states with toll roads that later became Interstates.

Initially, the system was to cover 41,000 miles of road, including 2,000 miles of existing toll roads. It was to be completed in 1975. As time passed it became obvious that goal would not be reached. We came close though; by then the system had about 35,000 miles of roadway.

President Eisenhower, Senator Albert Gore, Sr., Representatives George Fallon and Thomas Boggs, along with Frank Turner, chief of what is now called the Federal Highway Administration, are commonly seen as the fathers of the Interstate system.

There is some disagreement over when the first Interstate was made. Pennsylvania, with its Turnpike, Missouri, with its Interstates 44 and 70 and Kansas with its Interstate 70 all lay claim to being the first. The first three contracts under the new program were signed in Missouri on August 2, 1956. However, all of these roads were either started before the Interstate act was approved, or were upgrades of existing roads. The Pennsylvania Turnpike opened on October 1, 1940 and was the first limited-access, divided highway in the country.

The original name was the "National System of Interstate and Defense Highways." In October 1990, President Bush signed legislation changing it to the Dwight D. Eisenhower System of Interstate and Defense Highways."

In February 1994, the American Society of Civil Engineers declared the Interstate system one of the "Seven Wonders of the United States." Other wonders include the Hoover Dam and the Golden Gate Bridge.

The economic impact of this, the world's largest public works project, is incalculable. There is hardly one aspect of American society that hasn't been affected by the Interstates.

As of December 31, 1995 only 30 miles remain to be built, with 25 of those 30 miles already under construction and the other five in the design phase. When completed, there will be 42,796 miles of Interstates. They represent one percent of the nation's total road mileage yet carry over 20 percent of the nation's traffic.

The longest Interstate is I-90, which runs from Boston to Seattle, a distance of 3,081 miles. At 75 mph it would take you 41 hours to cover that distance non-stop. The second longest is I-80, which covers the 2,907 miles between New York City and San Francisco.

Interstates 5, 10, 15, 20, 25, 35, 40, 70, 75, 80, 90, 94 and 95 are all more than 1,000 miles long.

The shortest Interstate is I-878 in New York City, which is all of seven-tenths of a mile long. That's 3,696 feet.

The highest Interstate route number is I-990 north of Buffalo, NY. The lowest is I-4 across Florida

The only state without any Interstate routes is Alaska.

Interstates carry nearly 60,000 people per route-mile per day, 26 times the amount of all other roads, and 22 times the amount of rail passenger services. Over the past 40 years, that's the equivalent of a trip to the moon for every person in California, New York, Texas, and New Jersey combined.

Over 55,000 bridges had to be built.

There are a total of 58 one- or two-number Interstates in the continental U.S. Of those 58, 27 run primarily east west. The other 31 go primarily north south. There are three Interstates in Hawaii (H-1, H-2, and H-3).

East-west interstate route numbers end in an even number. North-south routes end in an odd number. The basis for this numbering system goes back to the 1920's.

If the first digit of a three-digit interstate route number is odd, it is a spur into a city. If it is even, it goes through or around a city.

1919 Transcontinental Motor Convoy

Woodrow Wilson - Motorist Extraordinaire

Sources: A 1996 special issue of Public Roads, a publication of the Federal Highway Administration, and The Best Investment a Nation Ever Made by the American Highway Users Alliance.  Public Roads Archives

Milestones for US Highway Transportation and the Federal Highway Administration  This is a time line of significant events in the history of highway transportation in America from 1892.


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