All About Roundabouts

What are roundabouts, and what are their benefits?

A roundabout is an intersection where traffic travels around a central island in a counterclockwise direction. Vehicles entering or exiting the roundabout must yield to vehicles, bicyclists, and pedestrians.

Roundabouts can have many advantages over traffic signals when constructed in the right location, including:

  • They provide traffic calming, resulting in reduced speeds.
  • They require less maintenance, have lower yearly operational costs, and have a longer service life.
  • They reduce greenhouse gas emissions by reducing vehicle idling time.
  • The median islands provide refuge for pedestrians, allowing them to cross one direction of traffic at a time.
  • They provide additional opportunities for landscaping in the community.

Tips for motorists navigating roundabouts
Taken from the Department of Motor Vehicles' California Driver Handbook

When you approach a roundabout:

  • Slow down as you approach the intersection.
  • Yield to pedestrians and bicyclists crossing the roadway.
  • Watch for signs and pavement markings that guide you or prohibit certain movements.
  • Enter the roundabout when there is a big enough gap in traffic.
  • Drive in a counterclockwise direction. Do not stop or pass other vehicles.
  • Use your turn signals when you change lanes or exit the roundabout.
  • If you miss your exit, continue around until you return to your exit.

For roundabouts with multiple lanes, choose your entry or exit lane based on your destination. For example:

  • Turn right at the intersection, choose the right-hand lane and exit in the right-hand lane. (Blue car)
  • Go straight through the intersection, choose either lane, and exit in the lane you entered. (Red car)
  • Turn left, choose the left lane, and exit. (Yellow car)

Roundabout Example DiagramRoundabout Multi-lane Control Sign

For more information about Roundabouts in the United States:

Driving Modern Roundabouts:


Contact Information

General Information:

Phone: (530) 741-4572
Fax: (530) 741-4111

Physical Address:

California Department of Transportation
District 3
703 B Street
Marysville, CA 95901

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