An east–west controlled access highway to serve the Northern United States was proposed in the early 20th century in several federal government documents, including reports from the Bureau of Public Roads in the 1930s and 1940s. The Interstate Highway System was created by the Federal-Aid Highway Act of 1956, which was approved by the U.S. Congress and signed into law on June 26, 1956. I-90 was assigned to the northernmost transcontinental route in the system by the American Association of State Highway Officials in 1957.
An east–west controlled access highway to serve the Northern United States was proposed in the early 20th century in several federal government documents including reports from the Bureau of Public Roads in the 1930s and 1940s The Interstate Highway System was created by the Federal-Aid Highway Act of 1956 which was approved by the US Congress and signed into law on June 26 1956 I-90 was assigned to the northernmost transcontinental route in the system by the American Association of State Highway Officials in 1957