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Interstates at a glance

• On June 29, 1956, President Eisenhower signed the Federal Aid Highway Act that authorized construction of a 41,000-mile "National System of Interstate and Defense Highways" to be completed within 15 years.
• About 75% of Wisconsin's Interstate system was built in the decade between 1959 and 1969.
• Today's U.S. Interstate system covers some 46,775 miles and represents a federal investment of some $120 billion.
• Wisconsin has some 743 miles of Interstate that cost about $1.5 billion (federal funds covered about $1.3 billion) to build.
• While accounting for less than 1% of the state's 113,700 miles of total roadway, Wisconsin's Interstate highways carry almost 18% of the state's vehicle miles each year and are among the safest roads to travel.
• In 2005, nearly 40% of Wisconsin's industrial parks were located within five miles of an Interstate.
• Wisconsin's longest Interstate highway segment - I-94 from Hudson to Kenosha - covers some 334 miles.
• Major Interstate routes are designated by one or two-digit numbers. East/west routes carry even numbers - north/south routes carry odd numbers.
• Wisconsin has long served as a transportation leader:
  • First state to implement a system of numbered state highways
  • Among the first states to complete its rural Interstate system
  • Nationally recognized for transportation policies that encourage public input and minimize environmental impacts.

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Office of Public Affairs, opa.exec@dot.wi.gov
Last modified: January 6, 2010