a car driving through a roundabout


This video, produced by the Colorado Department of Transportation, will show you how to properly and safely navigate through roundabouts.


Roundabout Benefits

There are a total of 32 roundabouts in the city of Thornton. Roundabouts are used as an alternative to traffic signals and provide several benefits.

Increased Safety: Because of their configuration, roundabouts substantially reduce the most severe type of crashes, T-bone and head-on collisions, that tend to result in serious injuries or loss of life.

Slower Speeds: Roundabouts slow traffic down, promoting lower speeds and traffic calming.

Reduced Emissions: Roundabouts also have an environmental benefit by reducing fuel consumption and greenhouse emissions. Starts, stops, and idling at traditional traffic signal intersections cause vehicles to emit pollutants. However, drivers navigating a roundabout are only required to prevent when there is conflicting traffic reducing pollutants being emitted.

Reduced Delay: Because vehicles can keep moving, roundabouts can reduce commute time and frustration associated with traffic signals.

Reliability: Unlike traffic signals, roundabouts do not need electricity, so they are not susceptible to power outages or other equipment issues.

Roundabouts Driving Tips

Traveling through a roundabout may be confusing and intimidating for some road users. There is a learning curve, and being patient and respectful of others unfamiliar with the roundabout is important. Here are a few tips for users on how to navigate a roundabout:

For Motorists


  • When approaching the roundabout, slow down. Be aware of bicyclists and pedestrians, and pay attention to crosswalks and signage.

  • When entering the roundabout, always yield to vehicles already circulating in the roundabout.

  • When a safe gap in traffic is available, merge into the roundabout.

  • When traveling in the roundabout, avoid lane changes and passing other vehicles when there are multiple lanes. Pay attention to signage and merging vehicles.

  • Do not stop once in the circular traffic flow except in case of emergency or crash avoidance.

  • When in a roundabout, use your turn signal to alert other drivers of your intent to turn onto the intersecting street.

For Bicyclists:bikes.jpg

  • Depending on your comfort level, ride with traffic inside the roundabout or use the crosswalks appropriately.

  • When riding with traffic, follow the same rules as vehicles and yield to circulating vehicles when entering the roundabout.

  • Since traffic slows down while circulating inside the roundabout, bicyclists should be able to travel at or near the same speed as motorists.

  • Alternatively, some roundabouts have ramps on the approach to the roundabout to allow bicycles to exit the road and use the sidewalks and crosswalks to navigate around the roundabout.

For Pedestrians: 

  • Cross only at crosswalks, and always stay on the designated walkways.

  • Activate the Rectangular Rapid Flashing Beacons before crossing if they are available.

  • Do not cross to the central island.

  • Cross the roundabout one approach at a time. Use the median island, if available, as the halfway point where you can stop and check for approaching traffic.