The U.S. Interstate highway system, one of the largest public construction projects in American history, will celebrate its 50th anniversary this Thursday. The system was created on June 29, 1956, when President Dwight Eisenhower signed the Federal Highway Act of 1956 into law. The bill, also known as the National Interstate and Defense Highways Act, granted $25 billion of federal and state money for the construction of more than 40,000 miles.

In just 50 years time, the Interstate changed the face of the nation by providing a transportation network that was unprecedented. Before its creation, high-speed, long-distance travel was nearly impossible since the existing transportation network was a mishmash of intersecting U.S. highways, state, county and local roads.

Supporters say the Interstate boosted business, gave Americans newfound mobility and allowed for rapid military responses to national crisis. Critics say it initiated suburban sprawl, wreaked environmental havoc and encouraged an unhealthy dependence on automobiles.

According to a press release from the Illinois Department of Transportation, there are currently 46,726 miles of divided “superhighways,” creating a nation-wide network of interconnecting roads. In Illinois alone, there are 2,169.53 miles of interstate highways crisscrossing the state with I-55 holding the longest stretch at 275.66 miles. The state ranks third in nation for the most interstate miles with Texas and California holding the top two positions.

The Champaign-Urbana area is located at the intersection of three interstates, I-57, I-72 and I-74.

On June 24 through the 26, an interactive traveling exhibit, featuring a University designed Airstream travel trailer passed through Ottawa and Chicago, Ill via I-80. The trailer allowed people record their Interstate experiences and memories and view 3-D imagery of simulated interstate highways under construction.

Rahim Benekohal, professor in Civil Engineering, said connectivity, mobility and easy access has made the Interstate system on of the best in the world. Benekohal also said the roads helped boost the economy, allowing for greater access to markets and easier travel.

“It’s an excellent system,” Benekohal said. “And it was a great idea when it was created 50 years ago.”