If you live on the East Coast, you may have driven through roundabouts in your neighborhood countless times. Or maybe, if you’re in some parts farther west, you’ve never encountered one of these intersections. But roundabouts, while a relatively new traffic control measure, are catching on across the United States.
Roundabouts, also known as traffic circles or rotaries, are circular intersections designed to improve traffic flow and safety. They offer several advantages over conventional intersections controlled by traffic signals or stop signs, but by far the most important one is safety.
If you live on the East Coast, you may have driven through roundabouts in your neighborhood countless times. Or maybe, if you’re in some parts farther west, you’ve never encountered one of these intersections. But roundabouts, while a relatively new traffic control measure, are catching on across the United States.
Roundabouts, also known as traffic circles or rotaries, are circular intersections designed to improve traffic flow and safety. They offer several advantages over conventional intersections controlled by traffic signals or stop signs, but by far the most important one is safety.
Modern roundabouts can have one or two lanes, and usually have four exit options.AP Photo/Alex Slitz
I research transportation engineering, particularly traffic safety and traffic operations. Some of my past studies have examined the safety and operational effects of installing roundabouts at an intersection. I’ve also compared the performance of roundabouts versus stop-controlled intersections.
A brief history of roundabouts
As early as the 1700s, some city planners proposed and even constructed circular places, sites where roads converged, like the Circus in Bath, England, and the Place Charles de Gaulle in France. In the U.S., architect Pierre L'Enfant built several into his design for Washington, D.C.. These circles were the predecessors to roundabouts.
Generative artificial intelligence is playing a major role in the presidential campaign, even if the greatest fears about how it could threaten the U.S. presidential election haven’t materialized yet