I mostly enjoy using the traffic circles north of Indianapolis. They are frustrating when I get trapped behind someone who doesn't know how they work, but in time I think they are relatively new (mostly constructed in the last three years) and so as users become more familiar with them that problem will lessen. But they are easy to navigate and easier on a car's suspension/brakes/whatever as you can typically just cruise through them. And they are definitely more efficient in terms of getting more cars through the same place in a given amount of time.

On the downside, yes, they cut pedestrians entirely out of the space. Which goes against everything I believe about the right of citizens to use public roadways with whatever means of transport they desire, including their feet. So one could say traffic circles are undemocratic and I would agree.

I Love Round-A-Bouts....!

spend a few weeks driving around the northeast if you want to see traffic circles in action. they're all over. all over england too, but their's go the wrong way.

great for cars, but for people?? not so great.

unless...you build a cool, interesting overcrossing that spans the whole circle...that would be dope.

or better yet, ban cars in your neighborhood. get every citizen a bike. that's a win-win situation for everyone.



this one spans rt. 80 in berkeley. not exactly your rank and file traffic circle, but a cool footbridge nonetheless. fully accessible too. two lane bike + 2 lanes ped.

the advantage is that (some) of the cars won't have to some to a complete stop - some continuous flow is better than a intersection that is subject to periodic 'flushing'.

i don't think pedestrians are left out. a pedestrain would never venture out into the roadway of a typical conventional intersection (except those rare diagonal cross-walk situations) and likewise wouldn't venture to the center of the circle (although once there it could be a cool place). In fact, i would argue that since vehicle speeds in a roundabout are lower than a conventional intersection, it's safer for pedestrians and gives them more priority in crossing safely.

oh wait a minute...you were talking about trafficicles...i prefer dreamsicles.

you see though, at a traffic circle, there is presumably no light and no stop signs. thus no requirement to stop.

if you put crosswalks in front of the entrances to the circles and make cars stop...well then what's the point of a circle? you may as well do the whole 4 way light thing.

and you definitely can't make a crosswalk directly to the center island, though i agree it would be a cool place.

in san francisco, there's loads of downtown intersections that go red for cars in all directions and people walk crossways, sideways, diaganol-ways. all ways. and they're fun to walk through! you get city and bay views from places where you would ordinarily not get them.

Also, for some reason, the roundabouts in New Jersey were my own personal hell. I think because everyone in Jersey is so aggressive that they just ignored the rules and stormed right into the circle causing the cars already on it to have to brake thus screwing up the whole concept. Sorry, Jerseyites, I never have been able to get a positive outlook on your state.

In the midwest, everyone is so polite that the traffic circle problems tend to be the opposite: not enough aggression in getting out into the flow when it's time.

ive never understood how 2 lane traffic circles (or for that matter, the 4+ lane ones you see in europe) work.... why would you ever want to be anywhere other than the outside lane? even if its a large traffic circle, say with a 200ft diameter, how would you have time to go to the inner lane and why would you want to?

once you go jersey, you never go back.

like i always say...it's a great place to be FROM.

that said, i ain't never, ever, ever, never, ever going back...thank you very little.

but really, it's a great place. but it's tough to love.

i lived in boston for a few years and went through harvard square everyday to work and thought the rotary worked there - although it was a bitch when i rode the bus and had to cross the street and backtrack to the bus stop. i did some checking and it seems like they are getting rid of some of the rotaries in massachusetts because they can't support current traffic loads.

I disagree that the center spot is a cool place. Are you guys kidding? We just got a rendering done of a project that has a traffic circle out front. The inner circle in the rendering looked very pedestrian friendly, the crosswalks went to it (across it) and there were benches and sidewalks in the circle, even though it couldn't have been very big (maybe 40' diameter). It looked like a horrible place to sit on a bench. It struck me as odd.

I don't really like traffic circles, perhaps because they aren't used quite right. I get that centrifugal dizzy feeling of making too tight of a turn too fast.

Are you talking about these?

I guess the ones around here aren't that big and so are pretty annoying. That one looks like it could work.

How funny.

In NZ, Australia roundabouts are a way of driving life. The size is dependent on the road width, number of intersections, traffic flow etc.

They always work. Thats why we have them.

Admittedly in my visits to the US [LA, Boston, NY] I never saw one, presumeably due to those particular cities. So I dont know how widespread they are over there.

mightylittle,
"if you put crosswalks in front of the entrances to the circles and make cars stop...well then what's the point of a circle? you may as well do the whole 4 way light thing."

that's exactly the point.
if there are no pedestrians - no need to stop. At a conventional intersection (timed presumably) someone HAS to stop because the lights are doing their own thing regardless of the traffic flow.

i agree that the scale of the circle can easily and quickly make pedestrian usage difficult. i can't imagine anything over 2 lanes working successfully for both car and pedestrian.

my gut reaction to the image that diabase posted is that the crosswalk are forced to be so far back from the circle (presumably to move them away from the merge lanes) that a pedestrian is forced to walk about 2x as much just to reach the walks.

i was mildly joking about wanting to hang out in the center of the circle.

though there are times when it is *cool* or perhaps more *interesting*to see the world from that kind of vantage point. thought provoking perhaps, but probably not a nice place for a picnic.

the main traffic circle in the town where i grew up had a go-go bar on one side, an awesome deli on one side, an antiques/junk seller on one side, and all manner of fast food in the immediate environs.

i believe it had the onerous distinction of being one of the most dangerous intersections in all of new jersey at one point. and there are many, many intersections in jersey.

and yes, i did drive around it going the wrong way once. i was young and stupid. i'm no longer young...

i also drove the wrong way around one in scotland about two months ago. i caught some stares that day.

but the picture up above looks like it could still be functional for pedestrians, depending on traffic volume.

the ones i'm familiar with in higher density areas would NEVER work with crosswalks like those. people just wouldn't stop.

i think the ped/bik overpass branching out like a spider from the middle would be the way to go.

See, that's my problem, though, jeffe. There are no pedestrians on these roads because it is virtually physically impossible for a pedestrian to navigate a traffic circle, especially if said ped has any concern for his/her safety. And I don't believe, in a democracy in which the roads are public rights-of-way that belong to all people, that we should exclude a class of people from using a right-of-way because of their choice of transport.

Yes there are exceptions - freeways and bike paths - but a typical local arterial road should be available for equal access by all, instead of this incredibly car-focused attitude that every bit of tax dollar should be spent making things easier and faster for cars.

I also believe every intersection should have the crosswalks raised to sidewalk height, making a smooth level path for pedestrians and a de facto speed bump for cars. But I can't really expect that in the US - only those crazy Scandinavian countries are smart enough to have worked out that a 350 horsepower engine can navigate a 6" elevation change more easily than a human carrying bags of groceries!

Only problem with the pedstrian linkages in the middle is that it reduces visibility. Best to have them set back along the road as above, or do it like the Chinese do - go underground.

HA!!! I havigate this traffic circle sometime - see what I mean about the centrifugal dizzy too-small thing? Suburbia...

The other circle I find myself in doesn't show up well on google earth, but it is about the same size.

i'm not so sure that is a design flaw of all traffic circles though, lb.
the first image posted by diabase devotes so much space to the circle that i agree it'd be a poor experience for a pedestrian.

in an urban environment, where the radius of the circle was tightened (to slow cars), and most importantly, the radii of the entry/exit curves was SIGNIFICANTLY tighter (to give pedestrians more visual prominence and a shortened crossing distance), pedestrian usability would be greatly enhanced.

the circles i'm most familiar with though (by direct experience) are single lane.

once again it all comes down to scale perhaps?

im from mass... so they are called rotaries, and they are really only fun and nessecary when you drive around and around and around them untill you make your friends puke :)

definitely comes down to scale...i agree with you there. without a high a volume of cars, you can easily give pedestrians the right of way without making for a hazardous condition. once you've got lots of traffic though, and two to three lanes, i think it's automatically a hindrance to bikes and foot travel.

btw - how do you link to a google sat photo?? any idea?

i'd love to show an example of what NOT to do.

I don't know if all traffic circles are intended for non-stop motor traffic. At Columbus Circle (redesigned with the AOL/Time Warner building), the circle is a means to navigate an intersection of more than 2 roads. Broadway meets 8 Ave meets 59 St at the center of the circle. Instead of all cars stopping all the time, they can cruise around the circle. It's a better solution (in NYC, anyway) than the disaster of, say, 23 St, Broadway, and 5 Ave (or any other Broadway intersection with a major uptown avenue) to reconcile the phenomenon of Broadway slashing across the grid of Manhattan.

The motor traffic issues aside, the traffic lights around the circle actually make it easier for pedestrians to enter the circle proper. And, there's something inside the circle worth visiting now. The new design (landscaping by Olin Partnership and fountains by WetDesign) is actually a nice place to sit down when the weather is nice. You would think that, with city motor traffic streaming by it would be loud, but the bermed circumference of the circle coupled with the sound of the fountains blocks out the sound of the city. In fact, WetDesign encourages the idea of the fountains for public interaction - embodied by the low profile of the interior edges of the fountain basins. I like it.

It may not be the kind of circle you are suggesting, but it is more than 2 lanes of traffic. And, when all of the lights are green, traffic is slowed a bit, but not stopped. Unfortunately, Google Earth only has the old design...

Wow - I love Olin's work, and those "community benches" at Columbus Circle are so amazingly optimistic about how people can get along together in public space! I'm actually surprised they were approved as they seem the perfect place for homeless people to sleep, but obviously someone was convincing that this was a good social experiment. Thanks for posting that, l8rpeace!

If ever there was a place for a community bench to work, it would be NYC...have you ever seen the juxtaposition of peoples sitting/standing on a crowded, rush hour subway train? Or, how about the proximate space you will be willing to be near the next person when in a park (bench or field)...inches.

Also, the Circle lends itself to this arrangement of benches working...they are deep (maybe 2.5 feet) and you never have to face anyone that is any closer than ~20 feet away (the people sitting around the column/status of columbus at the center). You will find people stagger themselves on the ring of benches, some facing out to the fountains, and some facing in towards the center.

Of course I understand proximity in relation to the subway - I was referring to the popularity - among police and scared zoning boards, I suppose - of nasty "anti-vagrant bars" being installed on public seats:



It's good to see that in a big public park (actually, is it publicly-owned?) there is an opportunity to offer a community seat without worrying about people sleeping on it. It seems that design approval bodies are rearely so gracious.

We dont really have the stop problem in Chicago, where stopping is optional. A 4 way stop is essentially a slow moving yield - where drivers instinctively just weave between each other. I think its interesting to see how the general public has decided the stop signs are a problem and have come to a mutual agreement and speed to navigate the 4 way ballet.


Some areas however, where blatant disregard for public safety is a problem, have put up traffic circles as roadblocks. Its an obstacle you have to slow down for to go around in the middle of the road. Strange solution.

I recently heard of a Scandenavian city which has gotten rid of all traffic signs to see how drivers fair with no rules - appearently their more cautious and travel times are down!

I have been lucky enough to design round-a-bouts versus circles. Indeed they were started when El Jeffe was in the office and completed long after he decamped to the desert.

A round-a-bout is a modern tweaking of the traditional traffic circle. They were tweaked in order to reduce the chance of accident and imporve pedestrian flow through the intersection without reducing traffic flow. The fundamental principal is thatin a circle the cars entering the circle have the right of way (thus forcing carsin the circle to slow down) whereas in a round-a-bout, the cars in the circle have the right of way thus causing cars entering to slow down and/or stop. Pedestrians cross in the yield lanes as shown in the photo previously posted, reducing the number of lanes they need to cross in any one walking movement, making them highly visible to oncoming traffic, and allowing them to concentrate on only one direction of on-coming traffic at a time. Round-a-bouts do tend to need an education period when they are first implemented in a community but on the whole have proven very effective where they have been implemented. To read more about them see this link.

After designing and helping to implement one, I became a convert and enthusiast. I am not sure that they are as effective in multi-lane situations but there are some pretty cool ones that integrate wide roads, though they do inthese cases take a lot of space which soemtimes is not effective.

This all cracks me up. Why are you all so afraid of a roundabout? obviously you've never driven on a 'magic roundabout':

http://en.wikipedia.org/wiki/Magic_Roundabout_%28Swindon%29

As diabase has pointed out, most civilised countries have been using them for years without any problems. I would say that you have to be very careful about designing them for the volume of traffic though. Multiple lanes? Free turning bays? They have a tendency to stop working efficiently when they are too small fort he volume of traffic and one dominant direction can prevent other drivers getting onto it.

Provided you get the balance right they work very well and keep a good flow of traffic while slowing cars down and reducing accidents.

yes Vado, that was for you

I love roundabouts! specially when there is no one around, or some shit who thinks' they can go around faster! not with me...it's nice watching my rearview mirror and watching them spin out!

This is the way it's done!

how did I not notice this topic before? I LOVe roundabouts! Not only are they fun, but I've been told that they reduce accidents as well. I can definitely see the logic in them at least reducing the severity of accidents- I'd much rather be sideswiped than t-boned.