When traffic engineer Gilbert Chlewicki first proposed to reduce traffic congestion by having people drive on the wrong side of the road, people thought he was crazy. But he’d grown up drawing out roads for his toy cars and then pursued a career in the field, so he knew what he was talking about. He just had to get people to think outside the box with him.

Years of governmental red tape and doubters didn’t stop him. He believed in the quirky, innovative idea and got others on board. The result: less congestion, flowing traffic and fewer accidents at more than 200 intersections in over 30 states across the country.

Click here to see the diverging diamond interchange in action!

(Photo credit Joel Rose NPR)