# Safety of Multi-lane roundabouts **URL:** \ **Category:** Factual Questions\ **Created:** [November 8, 2013, 8:49pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453 "2013-11-08T20:49:01Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [November 9, 2013, 10:36pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/21 "2013-11-09T22:36:52Z")
> [@For You](#): > > Drivers occasionally fail to heed traffic lights, either from haste or from distraction. My best friend was involved in a head-on collision while _sitting_ at a red light. **Nose-to-nose collisions simply cannot happen in a roundabout** , and drivers are forced to pay attention to traffic instead of trusting the light to manage the intersection. > … Well, we have had a couple such accidents with tourists driving on the wrong side of the road. 😃 But, yes, in general there are many fewer head-on collisions at roundabouts than at traffic lights. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [November 10, 2013, 1:48am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/22 "2013-11-10T01:48:34Z")
> [@Fleetwood](#): > > We’ve had them in New England for a long time. We call 'em rotaries. For the most part, those aren’t [roundabouts](http://en.wikipedia.org/wiki/Roundabouts#Modern_roundabout). ---
**Author:** ![Motorgirl](https://avatars.discourse-cdn.com/v4/letter/m/e36b37/32.png) [@Motorgirl](https://boards.straightdope.com/u/Motorgirl)\ **Post date:** [November 10, 2013, 3:21am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/23 "2013-11-10T03:21:20Z")
> [@dtilque](#): > > For the most part, those aren’t [roundabouts](http://en.wikipedia.org/wiki/Roundabouts#Modern_roundabout). All the rotaries I go through regularly here in the Boston metro area meet that article’s criteria for a roundabout. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [November 10, 2013, 9:38am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/24 "2013-11-10T09:38:23Z")
> [@Motorgirl](#): > > All the rotaries I go through regularly here in the Boston metro area meet that article’s criteria for a roundabout. [This database](http://roundabout.kittelson.com/Roundabouts) is a bit out of date, but it has only 3 roundabouts for the entire state of Massachusetts, but 23 rotaries. They consider them to be different things. However, perhaps the rotaries have been upgraded recently. Do you have any pictures of them? Perhaps they have Wiki pages? ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [November 10, 2013, 9:51am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/25 "2013-11-10T09:51:44Z")
For what it’s worth, two of the most common types of collision over here happen on roundabouts: A driver is in the outer lane intending to take the second exit and a driver on an inside lane cuts across to use the first exit and clips the front of the other car. This is most likely when a driver is unsure of which exit he wants and is reading the signs. He gets clipped by an impatient local. A driver is stationary and second in a queue to enter a roundabout. He is looking for a gap in the traffic as he hopes to follow the first car in. He sees a gap and pulls away assuming the first car will too. The first driver is more cautious (chicken) and stays where he is and gets rear ended. ---
**Author:** ![CoastalMaineiac](https://avatars.discourse-cdn.com/v4/letter/c/e8c25b/32.png) [@CoastalMaineiac](https://boards.straightdope.com/u/CoastalMaineiac)\ **Post date:** [November 10, 2013, 1:44pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/26 "2013-11-10T13:44:51Z")
> [@bob\_2](#): > > For what it’s worth, two of the most common types of collision over here happen on roundabouts: > > A driver is in the outer lane intending to take the second exit and a driver on an inside lane cuts across to use the first exit and clips the front of the other car. This is most likely when a driver is unsure of which exit he wants and is reading the signs. He gets clipped by an impatient local. > > A driver is stationary and second in a queue to enter a roundabout. He is looking for a gap in the traffic as he hopes to follow the first car in. He sees a gap and pulls away assuming the first car will too. The first driver is more cautious (chicken) and stays where he is and gets rear ended. There are a couple of two-lane rotaries in Augusta (they aren’t really up to the “modern roundabout” spec, but they function more or less the same way), and I know a few people that have rear ended another car that didn’t move off when they thought it would. I don’t think we have too many people in the left lane cutting people off. Rather, what we do have are certain drivers that are diametrically opposed to ever using the left lane—ever—no matter which exit they are going off. They also never seem to bother to signal left when they’re going to be [crossing over a lane](http://www.flashearth.com/?lat=44.310467&lon=-69.779696&z=19.1&r=0&src=msa) to stay on the circle, so it can be an unexpected and unpleasant surprise if you happen to be in the left lane intending to go straight. :mad: ---
**Author:** ![Motorgirl](https://avatars.discourse-cdn.com/v4/letter/m/e36b37/32.png) [@Motorgirl](https://boards.straightdope.com/u/Motorgirl)\ **Post date:** [November 11, 2013, 5:38pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/27 "2013-11-11T17:38:54Z")
> [@dtilque](#): > > [This database](http://roundabout.kittelson.com/Roundabouts) is a bit out of date, but it has only 3 roundabouts for the entire state of Massachusetts, but 23 rotaries. They consider them to be different things. However, perhaps the rotaries have been upgraded recently. Do you have any pictures of them? Perhaps they have Wiki pages? That database doesn’t seem to list any of the ones I go through every week, as any type. All are in Cambridge, Medford and Arlington, and none seem to be listed in that db. I’d say that db is very incomplete. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 11, 2013, 5:55pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/28 "2013-11-11T17:55:21Z")
One possible factor in favor of traffic lights over roundabouts is that, in a well-designed system, red lights aren’t as common as green lights. If the lights are synchronized well, you’ll probably be able to get several green lights in a row for each red light, and it gets even better for intersections where one road gets a lot more traffic than the other. Of course, this depends on how many _other_ intersections are controlled by lights, so it’s possible to get a bistable situation, where turning a light into a roundabout would be bad in a mostly-light town, but turning a roundabout into a light would also be bad, in a mostly-roundabout town. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [November 11, 2013, 5:56pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/29 "2013-11-11T17:56:48Z")
When they widened the main drag in my town they installed a number of roundabouts. People hate them with a passion, but that’s because they are either: young, and don’t like not being able to bomb down the boulevard at reckless speeds, or old and too pig-ignorant to learn a new way of driving. If they hadn’t installed concrete planters in the center of the things I think old farts would just ignore the circle and drive straight through. But there has already been a drastic decrease in serious accidents on that street. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [November 11, 2013, 6:18pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/30 "2013-11-11T18:18:22Z")
they’re starting to show up in my area along with “continuous flow” intersections which are not continuous flow. Recently I came across[2 roundabouts](https://maps.google.com/maps?q=columbus+ohio&ll=40.02921,-83.161231&spn=0.002736,0.004672&oe=utf-8&client=firefox-a&hnear=Columbus,+Franklin,+Ohio&t=h&z=18) (or circles?) at night that were stacked next to each other and the effect was unnerving. We were making our way around road construction trying to get back to the highway by driving a grid pattern. It felt like we drove onto a roller coaster. They will take some getting use to but if they move traffic faster then I’m all for them. I’d prefer driving down a road with timed lights but that’s just me. I like things to be consistent on the road. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 11, 2013, 10:44pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/31 "2013-11-11T22:44:33Z")
> [@Magiver](#): > > they’re starting to show up in my area along with “continuous flow” intersections which are not continuous flow. > > Recently I came across[2 roundabouts](https://maps.google.com/maps?q=columbus+ohio&ll=40.02921,-83.161231&spn=0.002736,0.004672&oe=utf-8&client=firefox-a&hnear=Columbus,+Franklin,+Ohio&t=h&z=18) (or circles?) at night that were stacked next to each other and the effect was unnerving. We were making our way around road construction trying to get back to the highway by driving a grid pattern. It felt like we drove onto a roller coaster. They will take some getting use to but if they move traffic faster then I’m all for them. I’d prefer driving down a road with timed lights but that’s just me. I like things to be consistent on the road. I don’t like the design of the roundabout for Cemetery and Main. It’s not clear to me who has right-of-way when the inner and outer lanes cross. Zoom in, and look at the maroon car heading north on Main, and the silver car about to enter heading west on Cemetery. If maroon wants to keep heading North, and silver is a little slow, they could collide, and it’s not clear (to me) who would be at fault. Silver is staying in his lane, but maroon is staying left of the dashed line. The other roundabout doesn’t have that issue, since the outer lane isn’t continuous. ---
**Author:** ![WotNot](https://avatars.discourse-cdn.com/v4/letter/w/e19b73/32.png) [@WotNot](https://boards.straightdope.com/u/WotNot)\ **Post date:** [November 11, 2013, 11:21pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/32 "2013-11-11T23:21:29Z")
> [@ZenBeam](#): > > I don’t like the design of the roundabout for Cemetery and Main. It’s not clear to me who has right-of-way when the inner and outer lanes cross. Zoom in, and look at the maroon car heading north on Main, and the silver car about to enter heading west on Cemetery. If maroon wants to keep heading North, and silver is a little slow, they could collide, and it’s not clear (to me) who would be at fault. Silver is staying in his lane, but maroon is staying left of the dashed line. > > The other roundabout doesn’t have that issue, since the outer lane isn’t continuous. Assuming the rules are the same as in the UK, traffic already on the roundabout has priority. If silver crosses the give-way line into the path of a car approaching from the left (in either lane) he’s at fault. ---
**Author:** ![CoastalMaineiac](https://avatars.discourse-cdn.com/v4/letter/c/e8c25b/32.png) [@CoastalMaineiac](https://boards.straightdope.com/u/CoastalMaineiac)\ **Post date:** [November 11, 2013, 11:39pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/33 "2013-11-11T23:39:06Z")
> [@ZenBeam](#): > > I don’t like the design of the roundabout for Cemetery and Main. It’s not clear to me who has right-of-way when the inner and outer lanes cross. Zoom in, and look at the maroon car heading north on Main, and the silver car about to enter heading west on Cemetery. If maroon wants to keep heading North, and silver is a little slow, they could collide, and it’s not clear (to me) who would be at fault. Silver is staying in his lane, but maroon is staying left of the dashed line. > > The other roundabout doesn’t have that issue, since the outer lane isn’t continuous. Silver has a [yield sign](http://goo.gl/maps/Q7Z7I). The person with the yield sign doesn’t have the right of way; which lane he is in is irrelevant. Think about a four-way intersection of two one-way streets (essentially what you have at that spot). The road you’re on has a yield sign, and you want to go straight across. Are you not going to yield to traffic in every lane that you will be crossing? ---
**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\ **Post date:** [November 11, 2013, 11:45pm UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/34 "2013-11-11T23:45:56Z")
> [@njtt](#): > > I also doubt that it is really true that American drivers are too stupid to quickly get the hang of roundabouts. Just on this point, [Mythbusters tested](http://www.treehugger.com/cars/mythbusters-roundabouts-vs-4-way-stop-intersection-which-more-efficient-video.html) roundabouts vs a 4 way stop. American drivers managed just fine with the roundabout after only a short practice. And the roundabout was more efficient, even though the drivers were more familiar with 4 way stops. That was for a single lane intersection, but I think it’s enough to put to rest the idea that American drivers can’t handle roundabouts. ---
**Author:** ![PaulParkhead](https://avatars.discourse-cdn.com/v4/letter/p/7ea924/32.png) [@PaulParkhead](https://boards.straightdope.com/u/PaulParkhead)\ **Post date:** [November 12, 2013, 12:12am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/35 "2013-11-12T00:12:01Z")
> [@WotNot](#): > > Assuming the rules are the same as in the UK, traffic already on the roundabout has priority. If silver crosses the give-way line into the path of a car approaching from the left (in either lane) he’s at fault. Yep, silver yields, no question. If he crosses the give way line when there’s oncoming traffic and collides with maroon, it’s silver’s fault. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 12, 2013, 12:30am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/36 "2013-11-12T00:30:22Z")
The way it looks to me, silver has to yield to the outer lane, but then enters and stays in that outer lane. Maroon is in the inner lane, and crosses the outer lane to exit. If I just entered the right lane on a freeway, and there is a car in the left lane, he can’t cross into my lane to exit unless it’s clear. It’s counter-intuitive for the roundabout to behave that way. ---
**Author:** ![CoastalMaineiac](https://avatars.discourse-cdn.com/v4/letter/c/e8c25b/32.png) [@CoastalMaineiac](https://boards.straightdope.com/u/CoastalMaineiac)\ **Post date:** [November 12, 2013, 12:41am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/37 "2013-11-12T00:41:00Z")
> [@ZenBeam](#): > > The way it looks to me, silver has to yield to the outer lane, but then enters and stays in that outer lane. Maroon is in the inner lane, and crosses the outer lane to exit. > > If I just entered the right lane on a freeway, and there is a car in the left lane, he can’t cross into my lane to exit unless it’s clear. It’s counter-intuitive for the roundabout to behave that way. I believe [this](http://goo.gl/maps/bb0tZ) should answer your question quite clearly. Silver has a yield sign, underneath it is a sign that says “to both lanes in roundabout.” The striping on [the roundabout in question](http://goo.gl/maps/nxvkf) indicates that the entering car is the one crossing lanes, not the exiting car. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [November 12, 2013, 12:54am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/38 "2013-11-12T00:54:15Z")
Fair enough. Maybe it’s more obvious when you drive it that it’s more like crossing a road than entering a freeway. None of the ones near me have two lane each way from four different directions like that. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [November 12, 2013, 3:10am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/39 "2013-11-12T03:10:43Z")
I’m still not exactly sure why I didn’t like it or found it confusing. Maybe it was the surprise of it. I’m sure time will improve how I feel about them but right now they make me uncomfortable and that’s directly proportional to the amount of traffic on them. ---
**Author:** ![Maserschmidt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/maserschmidt/32/18829_2.png) [@Maserschmidt](https://boards.straightdope.com/u/Maserschmidt)\ **Post date:** [November 12, 2013, 3:14am UTC](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453/40 "2013-11-12T03:14:17Z")
> [@Motorgirl](#): > > That database doesn’t seem to list any of the ones I go through every week, as any type. > > All are in Cambridge, Medford and Arlington, and none seem to be listed in that db. I’d say that db is very incomplete. [http://www.frcog.org/pubs/transportation/Roundabouts/Roundabout\_FAQ\_FINAL.pdf](http://www.frcog.org/pubs/transportation/Roundabouts/Roundabout_FAQ_FINAL.pdf) This doc from here in the suburbs seems to suggest that Fresh Pond is a rotary but not a roundabout… [Previous page](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453.md?page=1) [Next page](https://boards.straightdope.com/t/safety-of-multi-lane-roundabouts/673453.md?page=3)