Overview

Traffic in a roundabout moves in a counter clockwise direction around a central island. Vehicles entering the roundabout must yield to traffic already in the roundabout.

Differences between roundabouts and traffic circles

There are differences between traffic circles and roundabouts. The centre island of a roundabout is smaller than the centre island of a traffic circle. The roundabout has been designed with a tighter curve around the island to encourage lower speeds and may have a sloped curb to allow more room for larger commercial vehicles. Roundabouts can be a safer alternative to traffic circles in high-traffic areas.

Read more about roundabouts on page 61 to 63 of the Driver’s guide to operation, safety and licensing: cars and light trucks.

  • Alberta Transportation provides information about the benefits of a modern roundabout and how motorists can safely use a roundabout.

Driving a roundabout

The following 7 steps can help you safely navigate roundabouts as a motorist or cyclist:

  1. Note the appropriate exit.
  2. As with any intersection, choose the correct lane before entering the roundabout.
  3. Slow down as you approach the roundabout and be aware of crossing pedestrians.
  4. Yield to all traffic inside the circular lane and wait for an appropriate gap.
  5. Maintain a safe speed, as indicated by the posted speed limit signs, through the roundabout.
  6. Never change lanes within the roundabout.
  7. Signal for a right turn as you approach the desired exit, while maintaining a safe speed.

Truck aprons

Roundabouts in Alberta have a truck apron around the centre island that provides extra room for semis and multiple-trailer trucks.

The rear wheels of large trucks can drive across the truck apron, as they are designed to support the weight of large trucks and help long vehicles turn safely through roundabouts.

Roundabout signs

Information sign

Indicates direction to destination

Sample roundabout information sign

Regulatory sign - lane control

Indicates lane choice prior to roundabout

Sample roundabout lane control sign

Physical conditions sign

Indicates roundabout ahead

Sample roundabout physical conditions sign

Contact

For more information on driving through a roundabout or traffic circle:

Hours: 8:15 am to 4:30 pm (open Monday to Friday, closed statutory holidays)
Phone: 780-427-8320
Toll free: 310-0000 before the phone number (in Alberta)
Email: trans.driver.prog@gov.ab.ca

For more information about roundabout technical design guidelines:

Hours: 8:15 am to 4:30 pm (open Monday to Friday, closed statutory holidays)
Phone: 780-427-7129
Toll free: 310-0000 before the phone number (in Alberta)
Email: peter.mah@gov.ab.ca

Address:

Technical Services Branch
2nd Floor, Twin Atria Building
4999 98 Avenue
Edmonton, Alberta  T6B 2X3