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Comment by ajmurmann | Hacker News Reader

A roundabout is a much better solution than a stop sign. I still believe that the ubiquous stop signs in the US are there due to the oil lobby. Bringing a car to a full stop is incredibly wasteful.

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For cyclists, roundabouts aren't that much better unless we're given separate lanes.

Motorists still tend to blow through roundabouts at speed if they can't see anything coming. From personal experience you can easily navigate a roundabout at 35+ mph.

"From personal experience you can easily navigate a roundabout at 35+ mph."

If a roundabout is small enough, you can't. I have seen many small roundabouts throughout Europe that you cannot navigate without swerving faster than 20-30 km/h (which is assumed safe speed for pedestrian).

Plus, at least in my region there always seems to be some sort of obstacle blocking sight in the center of larger roundabouts. Maybe it's just a convenient place for memorials, statues, etc., but I can't help but think that slowing down drivers is at least a welcome side effect.

The obstacles are intentional. Blocking sight forces people to slow down.

Look at what they have in Berkeley. It addresses exactly this situation

I've been curious as to why American roundabouts include unnecessary vegetation or a hill in the middle? Why obscure oncoming traffic?

The obstruction in the middle also makes the existence of a roundabout more obvious.

Here‘s an example of how they are handled in Germany:

https://goo.gl/maps/cmLVxuhViyF2

The space it requires is not much bigger than the traffic light. That town replaced many of its intersections with roundabouts even in central and older parts of the city.

(You might say they went a little overboard with it, looking at the southern limits near that hospital.)

If it's a roundabout, the traffic across the roundabout is not actually oncoming, it's the traffic approaching from your left around the roundabout that you need to watch out for.

Roundabouts are the very last place where I would consider a bike lane to be a possible net win in safety. If the bike lane has priority at exits, then it will be constantly ignored, if it doesn't, then cyclists would be at the mercy of exciting drivers never forgetting to indicate, resulting in similar bloodshed. Besides being totally shitty towards cyclists who would then have to yield three times for going left at a crossroad-equivalent, at a very uncomfortable viewing angle and with permanent risk of un-indicated exits.

It might be wasteful, but so is killing people.

Stop signs and some speed bumps would soon slow them.

True, but as I pointed out, so would a roundabout. In the area where I grew up we also had a dangerous piece of road that got "fixed" by setting up a "dangerous curve" sign with a warning light on top. It went from multiple fatalities every year to zero.

Having lived near a very similar intersection, also with frequent accidents (it has a 2-way stop with heavy 50-70 mph cross-traffic and frequent left turns, depending on the time of day), cost may be a significant portion of the reason; a neighborhood campaign to replace the 2-way stop with a traffic light fell through due to a >$1 million price tag for adding a light to a countryside road, and it's doubtful a roundabout would cost less.

A roundabout might cost less. I wonder how much of that signal price was getting grid electricity to the site.

Interestingly, there is a flashing red/yellow light there (similar to [1]) and plenty of houses/powerlines, so it shouldn't be the power costs. I imagine the price of buying and laying signal cable might be similarly expensive, however, as the nearest signaled intersection is about two miles away, if I recall correctly.

[1] https://safety.fhwa.dot.gov/intersection/other_topics/fhwasa...

Anecdata: fixing frequent accident sites (e.g. 70 kph main road x 50 kph access roads) with traffic lights reduces minor accidents, but there was a major accident on one of them just recently...because "traffic lights be damned, nobody ever comes out that road anyw-BOOM." Traffic lights are a discretionary access control mechanism ("ignore at your discretion"), roundabout is a mandatory access control mechanism.

I wonder if that happened because the traffic light was just on a timer rather than taking actual traffic in account. If the smaller road hardly ever sees traffic the light would be red very infrequently and getting your attention when red.

It's a timer, yes - but if you do not have enough attention to see two RED lights on an otherwise empty intersection (one overhead and one right at your eye level), you have no business being behind the wheel, as you either a) are legally blind, or b) have the attention span of a proverbial goldfish.

The suggestion that anything important should be screaming and blinking (otherwise the poor driver couldn't have noticed) is patently ridiculous. There's quite a lot of other, less conspicuous things that a driver needs to be aware of (such as pedestrians or potholes).

A roundabout is always the best solution, but it's very expensive. Replacing the "Give Way" by a stop sign costs almost nothing and would probably help a lot, although not for truly reckless drivers.

Traffic lights chop up traffic flow, creating windows of opportunity for turns and crossings at minor intersections downstream. Roundabouts on the other hand create bottlenecks of relatively constant throughput, smoothing out any pulsation in traffic density (e.g. from upstream traffic lights), which makes minor downstream intersections much more difficult.

Determining the best option for a given case is more an at than a matter of simple preferences.

I agree. A roundabout is also a much better than solution presented in the article, whereby traffic would have to turn across oncoming traffic in order to continue on their original track.

I have roundabouts in my neighborhood. They have the exact same problem. If you don't come to a full stop and/or look around your A pillar deliberately, you may never see the car or bike hidden behind it.

I've also had the same problem turning onto a crossroad without coming to a complete stop at the stop sign first.

I believe the only real solution is driver training.

Training is important, but the idea behind roundabouts is "we'll have plenty of collisions here, but all of them will be 30km/h or less".

Obviously you want to having bicycles or pedestrians in your roundabout so adding a bike/pedestrian path next to the roads has to be part of the plan if you want to do it right.

But you modulate speed and rotate the car while navigating the roundabout, which solves the constant speed/constant bearing problem. At a roundabout, blind spots are all over the place and will never perfectly track another traffic participant.

Roundabouts and 4-way stops are used in different situations - a 4-way stop is typically used in residential neighborhoods or street grids where the roads are only single-lane and the lack of available space prohibits a roundabout.

In Europe the residential area would either 1. Have no signs resulting in the car to the right getting the right of way 2. One road gets a right of way sign and the other road had to yield.

I strongly prefer those setups because they are much more fuel efficient.

However, I don't think any of that would work in the UD because it would require real driving classes and tests. I had to drive around for close to 20 hours with a professional driving teacher on to of dozens of hours of theoretical classes. All that end in a 30min+ examination with a examiner in the back of the car putting me through as many challenging situations as possible.

In the urban eastern U.S. apartment buildings usually run right up to the road, except a ~ 1-3meter sidewalk. There isn't sufficient visibility to yield safely; both directions have to come to a stop anyway to check for cross traffic.

In the western U.S. (and eastern suburbs) the 4-way stops are largely vestigial; I'd agree that most of them could go away without any loss of safety. Many of the newer neighborhoods are signed that way anyway, though - I just drove through one this morning with 2-way yields.

My driver's ed class was IIRC 36 hours of instruction and 12 hours in the car, with a professional driving teacher. It had an hour long examination putting me through as many challenging situations as possible at the end.

It's also a matter of being used to bicycle traffic, and training. In the Netherlands in a residential area there are probably more bicycles than cars, so every car driver is used to being careful at junctions.

And on average a person needs 38 hours in the car with a professional teacher before they pass the exam, most people don't pass on the first try.

Most middle- and upper-class Americans take a driver’s education course (like what you’ve described) prior to receiving their driver’s license. In 10 years it won’t even be necessary because nobody’s going to be driving themselves anyway.

A lot of the cars on the road right now are ten years old or older. Even if self driving cars became a thing that anybody can afford right now it would take longer than ten years before nobody had to drive themselves.

In my country (Finland), the average age of cars used in traffic is 13 years.

Except pedestrians, bikers, cyclists, etcetera. (Plus you are overestimating the rate of change: I still see horse carriages on the road, 100+ years after the beginning of the car era)

And don't get me started on driver ed in PA, USA: in my case, it consisted of a video, signing an drivers' permit application - and voila, go out there and drive (under supervision). I was shocked, shocked.

In the UK you can get a provisional license that allows supervised driving with zero training. It's assumed your supervisor (anyone holding a driving licence for something like 7 years or more) will stop you doing stupid shit.

Interesting. I was so used to the continental idea "driver school takes at least weeks and is like any other training, except it's in a car" that the opposite approach was highly unexpected to me; it does make sense though.

>> In 10 years it won’t even be necessary because nobody’s going to be driving themselves anyway.

Try 50+ years. Driverless cars aren't happening anytime soon, and certainly not to a level where you literally don't need a licence to drive one.

And public transport definitely isn't going to be taking up the slack given the catastrophic decline in public investment therein.

There are plenty junctions that have been turned into a roundabout simply by painting a circle in the middle and putting up the necessary signs. They don't need that much space, especially in places that are low speed, low traffic volume like residential neighbourhoods.

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