Have you ever driven through a roundabout? Although most common in Europe, roundabouts are growing in popularity everywhere in the United States, especially in cities that want to increase the flow of traffic and prevent clogs at popular intersections. Driving through a roundabout can be scary if you're not used to it. In this article, we will go over the main features of a roundabout, where you are likely to find one, and the rules to drive safely through it. 

What Is a Roundabout?

A roundabout is a type of intersection that features a central island. There are no traffic lights. Drivers enter the circle, drive counter-clockwise (in places where people drive on the right side of the road), and exit at the appropriate lane. A famous example of a large roundabout is the Arc de Triomphe in Paris, France. Most roundabouts, however, have only one or two lanes. 

Studies by the Federal Highway Administration suggest that roundabouts can improve traffic capacity by 30 to 50%. They also reduce overall collisions by 37%, injury collisions by 75%, fatality collisions by 90%, and pedestrian collisions by 40%. Roundabouts also reduce maintenance costs to cities and other jurisdictions, as there are no traffic lights to power or maintain.

Roundabouts in the United States

The first modern roundabout in the United States was built in Nevada in 1990. In the next five years, they appeared in California, Colorado, Maryland, Florida, and Vermont. After an effort to change dangerous intersections with roundabouts in the city of Carmel, Indiana, injuries from car accidents dropped by 80%. 

A specialty database estimates the number of roundabouts in the United States at 7,900. 

How to Drive Through a Roundabout

Roundabouts can feel intimidating at first, especially if you do not practice through one during your driver's ed. They are fairly simple to navigate if you follow these basic rules:

• Yield to vehicles already in the circle

• Choose the right lane before entering the roundabout

• Do not change lane in the roundabout

• Do not stop in the roundabout

• Do not drive next to larger vehicles

• Slow down

You will find two types of roundabout signs: the single-lane roundabout and the multi-lane roundabout. The single-lane roundabout sign typically has three arrows in a circle.

You enter a single-lane roundabout by slowing down near the yield line. Look to your left. Yield to any vehicles already in the circle and check for pedestrians and bicycles. Enter the circle once it is safe. If there is no vehicle in the roundabout, you can enter without stopping.

A multi-lane roundabout sign is more complex, with lane indicators branching off in different directions. These explain the ways you can go in each lane.

The process to drive through a multi-lane roundabout is the same as for a single-lane roundabout, with the added requirement of choosing a lane before entering the circle. Once you reach the yield line, you enter the roundabout when it is safe to do so. People coming from your left have priority and must be yielded to. Once again, pay special attention to pedestrians and bicycles as you approach the intersection.

Larger vehicles may use two lanes to make their turn in a roundabout. Because it is likely that large vehicles such as trucks and buses use two lanes to enter and exit the roundabout, avoid driving next to them. Even if they are not using the lane you need, it is better to yield to them. 

It may be tempting to go through an empty roundabout at full speed, but it is important to slow down (remembering that speeding is the most common driving mistake people make).

Don't Be Afraid of Roundabouts

Although the public tends to fear roundabouts when they are first introduced, the approval rate doubles once drivers get used to them. If you are concerned about your ability to successfully navigate a roundabout, consider taking adult driver's ed lessons to refresh your skills and practice alongside a professional.