What is a Modern Roundabout
A roundabout is a circular intersection where drivers travel in a counterclockwise direction around a central island. Drivers enter the roundabout by yielding to traffic already in the roundabout and exit at their desired street. Roundabouts are often confused with other circular intersections that are commonly referred to as "rotaries" or "traffic circles"
Research has shown that roundabouts provide a much safer intersection for both drivers and pedestrians when compared to both traffic circles and traditional intersections. National studies have shown that roundabouts can reduce fatal crashes by about 90 percent, injury crashes by about 75 percent, and pedestrian crashes by 30 to 40 percent. Visit the Recommended Reading page for more research on roundabouts.
High-speed roadways are not the ideal candidate for roundabout intersections beacuse of the low speeds required for traffic entering roundabouts. When such roads are redesigned to take advantage of roundabout principles, steps are taken to reduce the speed of traffic, such as adding additional curves, markings, signs and lighting on the approaches. For more information visit Where Should Roundabouts Be Considered.