Evolution of the Interstate Highway system

History/origin: The Progressive Era of the early 20th Century was a formative period in highway planning and reform and gave rise to the concept of federal-state partnerships for highway building. The Federal-Aid Highway Act of 1938 called on the Bureau of Public Roads to study the feasibility of a toll-financed system of three east-west and three north-south superhighways.

In 1941 President Franklin D. Roosevelt appointed a National Highway Committee headed by Commissioner of Public Roads Thomas H. MacDonald.

Recommendation: Interregional Highways, which resulted in a study led by MacDonald, was presented to Congress in 1944 and supported a system of 33,900 miles of national expressways and an additional 5,000 miles of auxiliary urban routes.

Plans Forged: Congress approved the Federal-Aid Highway Act of 1944 and designated the National System of Interstate Highways to include up to 40,000 miles “to connect by routes, direct as practical, the principal metropolitan areas, cities and industrial centers to serve the National Defense” with connection to routes in Canada and Mexico.

Ramping Up: August 2, 1947, Commissioner MacDonald and Federal Works Administrator Philip B. Fleming announced selection of the first 37,700 miles on routes proposed by state highway agencies and approved by the Department of Defense. No federal funds authorized.

Foundation Laid: Federal-Aid Highway Act of 1952 authorized the first funding for system construction: $25 million a year for fiscal years 1954 and 1955. Another $175 million was authorized for fiscal years 1956 and 1957.

Green Light: June 29, 1956, President Dwight D. Eisenhower signed the Federal-Aid Highway Act of 1956. Title I increased the system's proposed length to 41,000 miles; nationwide design standards developed through AASHTO (A Policy on Design Standards: Interstate System); established a new method for apportioning funds among states and set federal government's share of the project cost at 90 percent. Title II—the Highway Revenue Act of 1956—created the Highway Trust Fund as a dedicated source of funding for the interstate highway system, on a pay-as-you-go basis through the federal gas tax and other motor-vehicle user fees.

Subsequent acts by Congress extended the Interstate system mileage to its current length of 46,837 miles.

Who's First?: Missouri, Kansas, and Pennsylvania claim to have laid the first portions of the interstate highway system.

Here are their stories

Missouri: On August 2, 1956, Missouri became the first state to award a contract with the new interstate construction funding. Of three contracts signed that day, the Missouri State Highway Commission first signed a contract for work on U.S. Route 66—now Interstate 44—in Laclede County. The other contracts were for work on U.S. 40—now I-70, the Mark Twain Expressway—in St. Louis; and for another section of the highway in St. Charles County. Work started on August 13.

Kansas: On August 31, 1956, the Kansas State Highway Commission awarded a contract for concrete paving of a two-lane section of U.S. 40—now I-70—west of Topeka. Construction on this road started before President Eisenhower signed the Federal-Aid Highway Act, but paving under the new contract started on September 26.

Pennsylvania: The Pennsylvania Turnpike between Irwin and Carlisle opened on October 1, 1940. It has since been incorporated into the Interstate system as I-76 and I-70.

Kennedy and I-95
On November 14, 1963, President John F. Kennedy dedicated the Northeastern Expressway (Interstate 95) in Maryland, which opened to traffic at 12:01 a.m. the next day. The event marked one of President Kennedy's last public appearances and his final public-works dedication before his assassination eight days later.

Maryland renamed the expressway the John F. Kennedy Memorial Highway on April 7, 1964. On November 22, 1964—one year after the assassination—49 motorists each received a rose as they passed through the Kennedy Highway toll plaza in honor of the late President who would have been 49 that year.

More than 6.1 million vehicles traveled through the Kennedy Highway's toll plaza in its first full year of operation. Today, more than 30 million vehicles pass through the plaza each year.

Source: American Association of State Highway and Transportation Officials (AASHTO)