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Comment by cjs_ac | Hacker News Reader

I live in the UK, which has roundabouts, mini roundabouts, double and triple roundabouts, traffic-light controlled roundabouts, and magic roundabouts. They work perfectly fine.

The difference is that traffic flows very differently in the UK to the US. In fact, the way traffic flows in those two countries captures a lot of their cultural differences. In the US, everything needs a grand overarching theory and imposed order, which is why Americans need traffic lights, and why they’re so keen on a very specific set of liberties that allow them to freely live such similar lifestyles. The UK embraces mild chaos and ruthless pragmatism, with everyone finding locally optimal solutions to their own problems, so things like roundabouts fit well with the national mindset.

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Try Spanish roundabouts. On the whole, poorly designed, implemented and regulated. On roundabouts with two or more lanes, laws favour those on the outside lane, so everyone takes the outside lane even if they are travelling 3/4 of the way round. As a result drivers who are in a position to take an exit, do not take that exit. In addition, indicators are not used by most drivers, or they simply leave their indicators on all the way round. In addition, it is not allowed to exit a roundabout from the inside lane even on to a two lane exit. In addition many roundabouts have three lanes to enter onto a two lane roundabout, or two into one, etc. No one knows the rules, or follows them, and no one seems to care, from the civil engineers right down to the end users. The only winners are repair shops.

In comparison, UK roundabouts are civilised examples of harmonious intellectual etiquette. Enjoy them.

[source] I learned to drive in Swindon, home of the Magic Roundabout.

If you complain about Spain, then go live and drive in Italy :)

Home of the double red light, “you really have to stop”

I live in the UK, drive occasionally in Spain due to Spanish in-laws, and agree wholeheartedly. I didn't know about the "outside lane has priority" rule though. I'd noticed it happening, but just thought it was a national quirk rather than gaming the system.

I agree with this, and I'll offer a rationale.

Because the US largely "grew up with cars", the economy was built around the expectation that folks can drive to work. The population density of the US reflects this, and mass transit just doesn't work in small/middle America. That means everyone needs to be able to drive. If you can't drive, you can't work. That isn't the case in the UK, and you'll notice a lot of these "driver beware" analysis is explained by the fact that driving in the UK is seen as a privilege whereas it is a right in the US. This sort of "mild chaos" is prohibitive for a lot of would-be UK drivers, and they just take the bus.

American, in an area getting more roundabouts. The two most heartfelt criticisms of roundabouts I've heard are:

- I have to pay attention every time I go through one. (Vs. having your mind elsewhere works fine with traffic lights? That might explain some of those T-bone crashes.)

- Certain multi-roundabout intersections are "because the Road Dept. hates us" horrors to drive through. Most-often cited - https://www.google.com/maps/@42.5058488,-83.758072,18z?entry...

From my PoV, roundabouts are generally a good thing. Mostly because local engineering standards for traffic lights are wretchedly low - so I can get where I'm going far faster through roundabouts.

As a European, that roundabout intersection looks fine? It might be slightly annoying to have to use all three roundabouts if you're exiting the highway northbound and want to take the southbound local road, but with the amount of exits there I can't imagine a junction would be better.

To an American it looks painfully small and slow for coming off a highway and would be overwhelmed often with cars and semi-truck traffic. One semi-truck would stop an entire circles worth of cars with its ass end swinging in and out. And highway travellers are going to be gun shy and not respond as quickly to gaps in the circle after doing 75+mph for an hour or more.

"They work perfectly fine."

The fact that you mention light-controlled roundabouts highlights that they do not, actually, "work perfectly fine".

Roundabouts are a practical example of the tyranny of the majority; minor traffic flows suffer against major. The centre of Salisbury is a perfect example, constantly gridlocked at two roundabouts except at odd hours on a Sunday.

Adding traffic lights to 'fix' this problem then leads to tailbacks on the major routes and congestion on the roundabout, such that the timing sequence for the minor routes are subsequently reduced, returning to the original problem.

Roundabouts, in the plurality, are used as a lazy 'solution' to at-grade traffic crossing, which the road designers themselves presumably don't have to suffer. They also cause pollution from brake dust from slowing and exhaust fumes from accelerating.

> The fact that you mention light-controlled roundabouts highlights that they do not, actually, "work perfectly fine".

I don't think anyone is claiming that roundabouts work in every and all situations: design handbooks often say they're good 'up to X vehicles per hour/day'.[1] But that does not mean they do not work, or not useful, for <X.

Intersections are an engineering problem, and there is a hardly ever an engineering solution that works everywhere and always. There is usually a spectrum of solutions for the various situations that are faced.

[1] https://www.fhwa.dot.gov/publications/research/safety/00067/... § 1.6.1, 3.3.1

Well we have very different experiences driving to, through, and around Salisbury. There's traffic, and it can get bad, but it isn't as bad as you say.

The council and national highways are working on it, but the problem is not one of roundabouts - its one of increases in traffic and lack of capability to make the roads bigger and/or build a bypass. Unless we're willing to knock down a load of housing and cultural sites we're stuck with something around or slightly more than the road capacity we have.

>They work perfectly fine.

I don't want to celebrate UK roads too much. The majority of roundabout users in the UK are not indicating properly. Too many people are stopping at them when they have priority. Lanes are just a suggestion and using the correct lane is an invitation for someone to drive into the left of you.

In other areas: enough people don't know how to use a slip road that it becomes a problem to those who do. Likewise the flashing ambers of a pelican crossing. Lane discipline is much worse than on the continent, to the point you can see it creating traffic jams. Lots of people are driving big cars without the confidence needed to remain in their own lane.

There are millions of drivers who've never passed a theory test. We could do with more ruthlessness.

I feel like you're singling out UK drivers without much evidence here, I've driven lots across continental Europe, although mostly Spain<>France<>Germany<>Nordics, but in all countries people tend to not indicate properly, inside of roundabouts or outside of them. I'll admit to people in the Nordics being slightly better at signaling, but they make up by being so scared and non-confident in their driving that their hesitation causes near-accidents, rather than the opposite.

Still, all across the world the average driver seems to below what I imagined the average driver to be, before I started driving myself.

All of that is user error. The roads themselves might be in disrepair, but are otherwise well-designed.

It may be user error, but that doesn't mean roundabouts aren't a footgun. It only takes one driver who doesn't do everything correctly to cause problems. It's not much fun driving around in the correct lane, only for someone to pull alongside you to the left (equivalent of "right" in the US, of course!). I failed a driving test because someone cut across me on a roundabout.

"I failed a driving test because someone cut across me on a roundabout." That driver may have cut across you on that roundabout but that doesn't mean roundabouts are a footgun.

If a given tool tends to have a high amount of user error, odds are there's a problem with the tool

I mean, what you're trying to minimise is (frequency of misuse x consequences of misuse). signalised intersections target the frequency element, roundabouts target the consequences.

When comparing two interfaces and one allows a larger amount of user error that interface is inferior.

The point is roundabouts require more work to navigate correctly than a four way intersection with traffic lights. Thus drivers are more likely to navigate incorrectly.

> When comparing two interfaces and one allows a larger amount of user error that interface is inferior.

Seeing a safety issue and ignoring all other considerations is an excellent example of the ‘overarching theory and imposed order’ I argued that Britain rejects in my first comment.

I’d rather have more small non-injury accidents if it means fewer injury accidents

Yes, we're discussing how the users change the way traffic flows.

Not gonna lie, I know about the flashing ambers of the pelican crossing, but they are uncommon enough, whenever I see one, I spend several seconds wondering what is happening, until it clicks it's one of these crossings.

In very heavy traffic conditions I suspect that roundabouts can gridlock all directions in a worse way than a standard intersection with a yellow box because everyone tries to enter the roundabout then they get stuck in it, and then the whole traffic is brought to a halt, including directions that should be unaffected. This happens very often where I live.

The UK has an over-reliance on roundabouts for junctions with motorways and large roads. They are also missing out on Turbo roundabouts, which are super cool and very common in the Netherlands.

The UK’s spiral roundabouts are the same as Dutch turbo roundabouts.

I have no idea what this means but I love it!

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