Talk:Roundabout/Archive 1

Just edited this page to add more detail on different types of roundabout. Not sure if the through-about roundabout really qualifies though, as it needs traffic lights. I was also tempted to add some words about the benefit or otherwise of adding traffic lights to roundabouts, but decided against in the interests of impartiality (unless anyone has some stats as evidence?). IMO traffic lights on roundabouts are one of the great evils. Woo yay! for the HH magic roundabout, my home town...

--Rtuck99 22:44, 14 Apr 2004 (UTC)

Roundabout sign reversed
The picture of the roadsign has the arrows pointing in the wrong direction! Here is the British Government's Highway Code site with a picture of the road sign. I don't know what the rules on copyright are for this - can someone check out if it's OK to upload this official picture? I imagine that it's copyright held by the UK Government, but since it's a roadsign it would be fair use, or something.

Alternatively, the picture on the article now looks homemade, someone could just reverse it... -- PaulHammond 14:19, 7 Jan 2005 (UTC)


 * Checked the current image. Apparently it's German, which explains the arrows being reversed and the lines being thinner than on the British sign.  Still think that the British sign is more appropriate for an article in English mostly written by Brits. PaulHammond
 * I was the one who changed that sign, since the German version has slightly larger arrows and is a bit more appealing to the eye, in my opinion. I wouldn't object to the change being reversed, however keep in mind that 80% of the world drive on the right, so having an arrow arrangement suited for right-hand traffic _is_ contributing to the international scope of Wikipedia. Nevermind that there's a lot of Americans on en: as well. :) --Doco 01:50, 3 May 2006 (UTC)

Actually, the graphic looks more like a traffic circle than a roundabout (per the definition in the article). --mav 21:48 Dec 11, 2002 (UTC)

That's because none of the cars in tha nimation are shown needing to yield -- the road markings look right for a roundabout though. -- Tarquin 21:56 Dec 11, 2002 (UTC)

Having read this article and a couple of others about road junctions etc I am now quite confused about: Yours, up the Elephant and Castle, Nevilley 08:50 Feb 18, 2003 (UTC) PS Next we need an animation of one of those Mother of All Roundabout things (eg Swindon) - that should freak people out completely!
 * what's a traffic circle? (I note the article does not yet exist hint hint)
 * how does it differ from a roundabout?
 * does it matter to the two questions above and the clarity of the encyclopedia that the UK does not use the expression "traffic circle" at all?
 * is there a risk then that US and UK roundabouts and those in other English-speaking countries are not precisely the same thing?

My understanding is that roundabouts are smaller versions of traffic circles that have yield control to enter them and pedestrian islands (not shown in illustration) between lanes of traffic right before those lanes enter the circle. These islands are wedge shaped so that they direct the drivers in the right direction before they enter the circle. The illustration is of a very primative roundabout that is really little more than a small traffic circle. --mav

My two cents:
 * the graphic looks to be a roundabout to me. Although it lacks geometric detail, the traffic flow is correct for a multi-lane roundabout.
 * All roundabouts are traffic circles, but not all traffic cirles are roundabouts.
 * As far as I can tell, the word 'roundabout' means the same thing everywhere. "Traffic circle" could mean a lot of different things, which is probably why that term is not used in the UK. Many proponents of roundabouts in the US also avoid the term "traffic circle" like the plague, because most early designs were total failures. If the the term is used, it is preceeded by the word "modern': "modern traffic circle"

Roundabouts differ from other kinds of traffic circles by
 * relatively low absolute speeds
 * relatively small speed differntials between users
 * no pedestrian access except on the approaches, behind the yield line

Low absolute speeds and speed differentials are dictated by the geomety of the roundabout, especially
 * deflection at entry
 * small diameter central island

But, to confuse things further, there are different kinds of roundabouts. For example, a mini-roundabout, has a mountable central circle. A larger roundabout may have a truck apron, while even larger roundabouts have multiple lanes in the cirulatory roadway, flared entries and no truck apron.

The magic roundabout of Swindon may be a modern roundabout, but it is a very complex one. (it's a bunch of mini-roundabouts surrounding one large roundabout) It's a one-of-a-kind oddity. Bluelion


 * Wouldn't it be more correct to say it's a bunch of mini-roundabounds surrounding one large traffic-circle? -- Ch&#39;marr 23:24, 2 May 2006 (UTC)

I hope the new gif illustrates how a UK roundabout functions better than the old one. Please let me know if i've made any mistakes. Mintguy 12:10 6 Jun 2003 (UTC)

Nice gif. Swindon isn't a one off, there's one in Hemel Hempstead too. Is a traffic circle just a large N. Am roundabout? Incidently, are there any roundabouts in N Am. I can't remember any in Ontario or Florida? jimfbleak 12:26 6 Jun 2003 (UTC)

I think I'd make the GIF a bit slower, myself. It's easy enough to follow if you're used to roundabouts, but I'm not sure how good it is as a teaching tool at this speed. --rbrwr


 * I've slowed it to almost half the speed it was. Better? Mintguy 17:09 7 Jun 2003 (UTC)


 * I think so. It's easier to see (for example) the cyan and yellow cars waiting for the blue one. --rbrwr

There's another Magic Roundabout on the A13 in Essex, at the Sadlers Farm interchange with the A130. -- Heron

ISTR there being one in Colchester, too. Or is that different? It's a series of 5 mini-roundabouts in a circle, allowing movement in either direction about the central island. Darac 09:47, 31 Oct 2003 (UTC)


 * Bugger me, they're breeding! When the Hemel one opened in 1973, I think it was the first of its kind. The local paper rented a chopper and filmed the traffic chaos from the air - every exit/approach to the roundabout was backed up for several miles, with those at the roundabout gingerly trying to work out what the hell they were supposed to do. Soon it all settled down of course, though minor collisions are probably still an everyday occurrence. GRAHAMUK 10:04, 31 Oct 2003 (UTC)


 * There's more yet. There's a list at . I live quite near High Wycombe and Denham and I can confirm that they can be quite fun to navigate: Wycombe more so for the lack of traffic lights. --Phil 14:16, Feb 27, 2004 (UTC)

UK Rule of thumb: Give way (yield) to the right while driving on the left hand side of the road
UK Rule of thumb: Give way to the right, driving on the left side of the road.

Following this rule of thumb, driving in UK's roundabouts didn't needed any special regulation, you just have to follow this rule before, in, or after the roundabout.

The problem was in the continental Europe &#8220;driving on the right and giving priority to the right&#8221; as well, the roundabouts, this way, they become &#8220;centripetal&#8221; -easy in/hard out&#8211; (When  I arrived  place d&#8217;Etoile (Charles Degaulle) for the first time in 1970, I ended up in the center of the &#8220;rond point&#8221;, giving my best wishes to the unknown soldier monument, I had to give away the &#8220;priority to the right&#8221;, to get out of there)

On the other hand in the UK &#8220;driving on the left and giving priority to the right&#8221;, the roundabouts they become &#8220;centrifugal&#8221; -hard in/easy out- (hard to get into them and easy to get out of them)&#8230; I don&#8217;t see the need to adopt in 1966 in UK a mandatory &#8220;give way&#8221; rule at all circular intersections wich was already set by default, by the english way of driving (driving on the left and giving priority to the right), unless before 1966 you were giving priority to the left&#8230;

Anyone can tell me since what date the rule &#8220;give priority to the right&#8221;, was applied in UK?

Thanks

Manuel Capdevila

Safety and use in the U.S.
I have come across the article "Roundabouts: A Direct Way to Safer Highways" from what I'm sure is the regularly enthralling U.S. Federal Highway Administration magazine Public Roads. Some of its information may be useful here. The article goes into some detail about the differences between traditional traffic circles and roundabouts, provides some details about the use of roundabouts in the United States over time, and has lots of safety statistics about their use throughout Europe (such as a comparison of traffic intersection accidents in the UK, where roundabouts are common, versus France, where they are not nearly so common).

To be honest, I had never really put much thought into these before moving from Virginia to Vermont some months ago. Virginia has done away with nearly all old-style traffic circles and has no roundabouts that I know of, whereas both are relatively often found around New England, and I've rather come to like them when they're implemented correctly and the other drivers don't freak out at the sight of one. --Scott Dellinger 20:03, 6 Aug 2004 (UTC)

Roundabouts are best at replacing traffic lights at intersections where the floe of traffic is greatly enhanced rather than having to wait pointlessly at a red light when there is no other traffic Dainamo 00:08, 7 Sep 2004 (UTC)


 * Perhaps I'm missing something, but it seems to me that roundabouts may work better in places where cars have the right-of-way rather than pedestrians (e.g. Britain and its former colonies). Pedestrians crossing an exit to the roundabout seem likely to cause waiting cars to block up the circle.  Especially in areas with a significant amount of foot traffic willing to exercise its right-of-way, it seems that this may stall the circle for some time.  (In the United States, the only time a pedestrian does not have right-of-way at a crosswalk is if they are facing a red light or do-not-walk signal.  At any other time, all cars are required to stop to allow a pedestrian to cross.)  Is anyone aware of this being a problem in the U.S., or have roundabouts generally been avoided in pedestrian-heavy areas and used primarily in residential or rural areas?


 * In the U.S. we also seem to have a rash of fake mini-roundabouts, where for traffic calming reasons, a small round obstruction is plopped in the center of a two- or four-way stop, without changing the stop signs. This leads to ambiguity as to right-of-way: is it the same as before, or do roundabout yield-to-the-left rules now apply? Speight 04:30, 17 April 2007 (UTC)

Fast roads

 * Roundabouts are statistically safer than both traffic circles and traditional intersections, though they do not cope with the traffic on motorways or similar fast roads.

To say that roundabouts "do not cope" with traffic on motorways/freeways and other fast roads is simply incorrect. Roundabouts are a reasonably common kind of junction/intersection on British dual carriageways (fast laned roads with a central reservation separating traffic streams) including some motorways. I'll change the text to "do not cope as well". --Tony Sidaway|Talk 05:09, 1 Jan 2005 (UTC)


 * I think this was probably originally making the point that they don't usually cope well with large amounts of traffic (something that often goes hand-in-hand with motorways/dual carriageways). Also, I'm pretty certain that motorways cannot have roundabouts (other than past/at the end of the designated motorway - which is reasonably common). zoney &#09827; talk 21:17, 4 Jan 2005 (UTC)
 * The designated motorway ends a distance from where the slip road meets the roundabout (to make sure you're not breaking the law by being stationary on the carriageway of the motorway) Chris 02:57, 21 Mar 2005 (UTC)


 * The M27/M271 interchange near Southampton is a non-grade-separated normal roundabout, with traffic lights at that. And since the whole interchange is (obviously) subject to motorway regulations, when the lights are red you have no choice but to be stationary on the carriageway! Actually, The Pathetic Motorways site has a good page on the M271, with plenty of photos. Loganberry 14:51, 19 May 2005 (UTC)


 * Despite recent propaganda on roundabouts being safer this is not true and quite the oposite for bicyclists and pedestrians. Roundabouts do cut down on the number of left hand turn accidents (obviously since roundabouts dont have left hand turns, im in the US, change left to right if in UK), those turns do make up the largest category of accidents in traditional intersections, however other categories (rear ends especially) do increase in roundabouts with worse consequences and the response time of clearing accidents at roundabouts increases, resulting in more delays of longer length of time after each accident.  DOT's around the country know that roundabouts can not handle large traffic volumes and that traffic is increasing everywhere, these roundabouts will need to be torn up eventually when reaching their peak, which is much lower volume than that for a traditional fourway stoplight intersection. Big rig trucks and smaller trucks (think ups or fed ex)find it more difficult and annoying, as do fire trucks and ambulances, as they often have to ride their left side on a raised level of pavement curb in order to fit (that raised curb is designed for them to ride on, but still causes aggravation).  Urban planners and engineers in places like the NYSDOT have become enamored with roundabouts as the next new thing and newspapers and places like this spread the idea that its great, no accountability or study by people outside of urban planning has been done to verify their claims of "roundabouts are great!", we are back in the days of the newspapers taking engineers word for their work on highways like we were during the days of Robert Moses, and that era turned out bad with his and his intellectual decendants burdening us with slums with no parks and highways with no public transportation and bridges too low to allow buses underneath.  The same will occur with roundabouts.  This article is nothing more than a pro-roundabout view, how about some of the other side?  Whereever roundabouts have come up there have been people complaining and their views, when actually published, are countered by a "DOT says its unfounded and things will be better, just people hating change" attitude in the same newspaper article. Camelbinky 14:42, 23 July 2007 (UTC)

Capacity?
Does anyone have information on capacity (for instance, if this is possible to figure out, that a one-lane roundabout will be able to handle an intersection of two two-lane (one in each direction) roads with a certain speed limit)? I may try to find this, but if someone has it, that would be nice. --SPUI (talk) 19:02, 24 Apr 2005 (UTC)
 * The web has quite a lot about this, findable by doing a search for such combinations as "roundabouts capacity comparison". For example: -- Picapica 22:32, 31 May 2007 (UTC)

For a single lane roundabout, the capacity is about 1100 circulating vehicles per hour in the United States.

First modern roundabout
Parliament Square and Clock Tower (Leicester) both claim this honour. Would be good to dig and settle this? Morwen - Talk 14:26, 21 October 2005 (UTC)

Public Reception?
The article mentions some of the general advantages and disadvantages of roundabouts and traffic circles, but does not clearly lay these out or go into detail. I know that different people have different feelings about them too. I'd be interested to see statistics of the public response to their use (what percentage likes them, and what percentage dislikes them?). I know some people, and especially a lot of road geeks, are quick to state their advantages. Also people who live in areas with these are usually complacent to their existence. However, I know that some people (myself included) hate them. Perhaps because for people who learn to drive in places without traffic circles, the first encounter with one is often complete unfamiliarity and confusion. I know a lot of people who really despise them... perhaps something should be added to the article highlighting the public debate over their use? Thelastemperor 12:28, 20 February 2006 (UTC)


 * The Insurance Institute for Highway Safety conducted a before-and-after study on the subject. They state, "The proportion of drivers in favor doubled overall, from 31 percent before construction to 63 percent after. Those who were strongly opposed dropped from 41 percent to 15 percent." ('Status Report', July 2001, http://www.iihs.org/sr/pdfs/sr3607.pdf, page 2).


 * I'll add this to the main article sometime soon when I have time, unless someone beats me to it. Triskele Jim 16:19, 26 December 2006 (UTC)

Merge
I have removed the merge as it there is a section Difference between roundabouts and traffic circles and it is not being discussed here, feel free to add it back if this is a mistake. Rex the first talk 11:26, 4 June 2006 (UTC)
 * I agree that they should not be merged because they are quite different. --Coolcaesar 17:09, 4 June 2006 (UTC)
 * They are only different in advertising for the "modern roundabouts". Roundabouts in the UK are equivalent to traffic circles in the US. --SPUI (T - C) 22:25, 11 June 2006 (UTC)
 * See also the caption on traffic circle - "This traffic circle in front of the county courthouse in Angola, Indiana, would be considered a roundabout in the UK." --SPUI (T - C) 22:27, 11 June 2006 (UTC)
 * Then that should be moved to roundabout. Ohh and no merge. Jooler 07:40, 12 June 2006 (UTC)
 * I am also against the merge. Circles typically have very large radii and are, nowadays: being replaced with tighter-radii roundabouts; realigned as T-intersections and signalised on the approaches; bisected through the middle and forming a central plus-intersection with the circle serving as auxiliary lanes or parking.  Roundabouts are very compact and will typically fit within the existing right-of-way for a signal. --Thisisbossi 11:30, 14 June 2006 (UTC)

SPUI, could you explain why the "Difference between roundabouts and traffic circles" is not adequate in explaining that the two terms are linked but have differences? It looks like there is a case for merger but the two articles could continue to develop separately which might be better Rex the first  talk 23:44, 12 June 2006 (UTC)

Maybe not necessarily merge them-but keep a link at the top for 'see also 'traffic cirlce'Mcode


 * I added cross "See also" for roundabout and traffic circle so it will be clear to the casual editor and reader that each article knows the other is out there and provide the reference. I personally don't see the why the two articles can't be merged it looks to me like traffic circle would make a nice addition to roundabout.  For one thing it would be much easier for the casual reader (like me) to differentiate the two terms if they are were being addressed in the same article.  Jeepday (talk) 01:49, 14 May 2007 (UTC)

Merge revisit
In NH, at least, the terms "traffic circle" and "rotary" are used extensively for what some people are saying is more properly termed a "modern roundabout" (traffic circle, rotary, roundabout ). For example, the Portsmouth Traffic Circle, which is signed as such. I've never seen "roundabout" on any NH road sign, but I've seen the other two on at least a dozen. I suspect it's a regional dialect thing. Which leads me up to...


 * Portsmouth Traffic Circle appears to be exactly that, not a roundabout (modern or otherwise)! GEarth imagery does not show any yield-on-entry markings on the road.82.210.249.81 (talk) 11:12, 12 December 2007 (UTC)

I think traffic circle and roundabout should be merged, not because the various terms have the same meaning, but because they share a lot of common characteristics, and the differences are more easily addressed in a single article, as opposed to two articles which duplicate most of the content. Think about what will be more useful to the reader: Hopping back and forth between two articles, or reading one which provides treatment of all terms?

— DragonHawk (talk|hist) 20:09, 20 November 2007 (UTC)


 * I am against a merge. Apart from being circular, they do not share any characteristics. No content should be duplicated in two separate articles.82.210.249.81 (talk) 11:12, 12 December 2007 (UTC)


 * I don't know why the merge proposal failed before, but I agree that it should be revisited. I also congratulation DragonHawk on bringing it here first, because there are sometimes other relevant issues that can be resolved before initiating some formal process.
 * I think that these two articles should be merged because, from what I can gather, the major difference between the two is whether the circling on entering traffic yields to the other traffic. If there are other differences, please bring them up here. &mdash; Val42 (talk) 18:59, 22 November 2007 (UTC)


 * In a nutshell, there are many kinds of circular intersections - roundabouts, old traffic circles and rotaries, gyratories, residential traffic calming circles, etc. In US professional parlance, if it meets certain design requirements, it is a modern roundabout. If not, it is something else. The chief criteria are yield on entry and slow traffic speed. It might be best to have an article on circular intersections in general, with links to separate articles on roundabouts, circles, traffic calming circles, etc.Triskele Jim (talk) 20:15, 25 November 2007 (UTC)


 * Are there really enough differences for there to be a separate article on each type of circular intersection? &mdash; Val42 (talk) 06:24, 27 November 2007 (UTC)


 * Triskele Jim: I'm not arguing that the different terms mean the same thing. What I'm saying is that it would be better to have all those different traffic structures treated in one article, because they will share a lot of the same information anyway, and it will be easier to contrast them given the context of a single article.  Remember, Wikipedia is not a dictionary -- we don't need to have a different article for every term.  :)  — DragonHawk (talk|hist) 05:47, 28 November 2007 (UTC)


 * I think there are enough varieties of circular intersections that the resulting article would be large and ungainly. Granted, "Seattle circles" need hardly more than a paragraph and a picture, and therefore probably do not deserve a separate article. Triskele Jim (talk) 13:57, 28 November 2007 (UTC)


 * I know that Wikipedia is not a democracy, but in this discussion I count two (DragonHawk and I) for merging the articles and one (Triskele Jim) against. However, I'm seeking a greater consensus before doing a merge.  What about if we try this:
 * Merge all of the articles about circular intersections into one article: "Circular intersections"?
 * Change all of the previous articles into redirects to this new article.
 * Let the merged article settle for a week or two so that it is stable. By this, I mean that we edit "Circular intersections" to add and consolidate information and fix any rough edges because of the merge.
 * Re-evaluate this new article to see if any sections are "large and ungainly" enough to become separate articles, then split them off, reusing any of the articles that were redirects.
 * This would provide a test of both proposals: That these articles can be combined and that they are too large to combine. Does this sound reasonable? &mdash; Val42 17:17, 30 November 2007 (UTC)

Image:Roundabout.bristol.arp.jpg
Isn't this a traffic circle, since the traffic on the circle stops at traffic lights and some entrances appear to flow straight onto the circle? If it is, that just adds to the confusion, but I don't think the article has done a good enough job making the difference clear enough to be sure! BigBlueFish 11:31, 24 June 2006 (UTC)


 * I put that picture on. In England this is definitely a Roundabout simply because we don't use the term Traffic Circle in England (at least not in Bristol where I live). So the pic can't be a Traffic Circle because it's a Roundabout! (Its full name is the "Old Market Roundabout" because its in the Old Market district of Bristol) - Adrian Pingstone 12:56, 24 June 2006 (UTC)


 * You must give-way to the traffic from the right, hence it is a roundabout. Traffic lights (overruling other rules and signage) are mediating priority, but without them, it is priority to the right (yield on entry).82.210.249.81 (talk) 11:03, 12 December 2007 (UTC)

Cyclist propaganda?
Unfortunately this is starting to read like a pro-cyclist propaganda article. There is a heavy proportion of cycling related matter in this article, and while i appreciate cyclists are road users too, and that roundabouts can be dangerous for those cyclists that cut across lanes, launch themselves from or to pavements, fail to yield (or give way) and ignore traffic lights and one way streets, there is a lot of unnecessary chaff that could do with being edited out. 212.159.16.124 09:13, 5 December 2006 (UTC)

The statistics given from the New Zealand analysis does not support the claim that roundabouts are more hazardous to cyclists. Without reading the whole study, it's impossible to say whether the crash risk per entering cyclist is increased, decreased by a lesser amount than other injury crash types, or does not change by a statistically significant amount, as other crash types are reduced. Triskele Jim 17:02, 19 September 2007 (UTC)

Automotive and cyclist crossing independently
Sorry but i couldent find an english link, but in the following link's last page (23) a map of a solution from Holstebro is showen, where cyclist and automovtist cross in seperate levels avoiding some of the problems mentioned about cyclist in the article. 

Deflection?
The article says, "Use deflection to maintain low speed operation" .. what is deflection?

Drivers must maneuver (are deflected)around the splitter islands and central island, at speeds of 15-25 mph (24-40 km/h). Many older traffic circles allow speeds as high as 45 mph due to insufficient deflection. When I get a chance, I'll figure out how to say this in the article.

Deflection is the correct term. I'd recommend simply providing a definition.

US Roundabout Building
This artcile by The Economist is about the rapid increase in the building of roundabouts in the USA. Are the facts contained within it worthy of including in this artcile?Grizzlyqi 17:56, 18 August 2007 (UTC)

My two (european) cents
As a french this article really confuse me. First the difference in use of the two words "roundabout" and "traffic circles" is not clear. For example, as far I understand, this thing: http://en.wikipedia.org/wiki/Image:Roundabout.bristol.arp.jpg (used as a figure in this article) is a traffic circles not a roundabout. But English people only use the word roundabout. This vocabulary problem is very US/UK centric, I think. But the article need to be coherent...


 * The difference is pretty simple. Roundabout = yield on entry, Traffic circle = yield to entering traffic.82.210.249.81 (talk) 10:59, 12 December 2007 (UTC)


 * English people only use the word roundabout because they only have roundabouts, there are no traffic circles in the UK. http://en.wikipedia.org/wiki/Image:Roundabout.bristol.arp.jpg is clearly a roundabout, since you cannot enter without yielding to traffic already on the roundabout (as indicated by road markings). In this case, traffic lights are also used. Traffic lights over-rule the other rules of the junction and other road signs (as they do everywhere). However, if the lights fail, people entering must *always *yield to traffic from the right (i.e.: traffic on the roundabout).82.210.249.81 (talk) 10:59, 12 December 2007 (UTC)

For me, and probably for every people in Europe, a classical roundabout looks like this: http://it.wikipedia.org/wiki/Immagine:Rotatoria_Fiorita.JPG (picture from the italian WP). As you can see it's a quite simple and small road junction. They are very common in France (but not on very big city like Paris) for medium or low traffic croos road with more than 4 way. Usually people like them because they are simple to use, fast and safe.


 * Yes. The image is clearly a roundabout, as you must yield at entry. France also has traffic circles, such as the Place de l'Étoile, where there is no yield on entry rule. People don't like them because they are not safe.82.210.249.81 (talk) 10:59, 12 December 2007 (UTC)

A big part of the article talk about the proc/cons of use of a roundabout on a motorway, this is very strange because I never see a roundabout on this kind of road (it simply doesn't fit to this use IMO). Outs 12:47, 21 August 2007 (UTC)

Photos
Just wanted to share some photos of a unique roundabout recently installed in Maryland. I think this is the better of the five, but I'll include the others in case anyone thinks there's a good place to fit them in here. It's completely formed out of pavement markings. --> #1 #2 #3 #4 <-- -- Bossi  ( talk • gallery • contrib ) 04:33, 8 December 2007 (UTC)