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Magic Roundabout (Swindon)

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Re: Magic Roundabout (Swindon)

#191

Post by laumars »

dmitriid wrote: post #40
laumars wrote: post #11

Earlier quoted context omitted.

They look scarier than they are in practice. What I hate more is those massive roundabouts with traffic lights on where dual carriageways meet. On those things you still have a mix of cars who don't know where they're going and lanes to be away of, but in addition you have traffic lights and cars moving at much higher speeds than on magic roundabouts.

Barcelona. It's fine to have a roundabout where several roads meet, each with multiple lanes, and the circle itself to have 6 or more lanes [1] [1] As an example https://www.google.com/maps/@41.3748215,2.1491456,232m/data=...

That does look a busy junction but I was thinking more like when motorways cross.

https://www.google.com/maps/place/Stansted+CM24+8JT/@51.8715...

This example is by no means the worse in the UK -- far from it -- but it does illustrate how cars can be going round at high speeds even when it's not really safe to.

It amazes me there aren't any fatalities on these kinds of junctions because it's a horrible mix of speed, heavy traffic, lighter and heavier vehicles (eg you get plenty of lorries on there too) and clueless drivers. A real bad recipe. But it might just be my lack of faith in other drivers that makes me nervous on those junctions rather than them being inherently unsafe.

Re: Magic Roundabout (Swindon)

#192

Post by JdeBP »

twic wrote: post #132
laumars wrote: post #5

Earlier quoted context omitted.

The beauty of these kind of junctions is you can drive clockwise or anti-clockwise. Essentially it's not a roundabout but rather one junction comprised of lots of roundabouts. The Colchester equivalent better demonstrates this: https://en.wikipedia.org/wiki/Magic_Roundabout_(Colchester) Personal anecdote: I had to drive around one of these junctions during my driving test

In other Colchester roundabout news, the one at North Station is fun - it's a normal roundabout, but with a road cutting right through the middle of it too: https://www.youhaventlived.com/qblog/2005/QBlog160705A.html There are lights to make sure nobody crashes - effectively switching it between being a roundabout and being a through road - but it's still pretty weird.

Nuneaton has one such, at the junction of the A444 and A4254. Nottingham also has one, on the junction of the A52 and B6003.

Re: Magic Roundabout (Swindon)

#193

Post by JdeBP »

kerkeslager wrote: post #116
TheCapn wrote: post #83

Earlier quoted context omitted.

RE: #2 Absolutely. Within Saskatchewan, east of Regina, we just completed three new bridges for suburban communities to access the main highway. In two of the three bridges were atypical designs using a Diverging Diamond at one point, and dual roundabouts at the other. When announced lots of people were fearful of the new designs and there was unsurprisingly a lot of outcry from ninnies who were afraid of the unknown…

Another example of this is the downtown area of a small PA town I stopped in recently. They had recently re-paved the entire center street with brick and stone. The sidewalks were wide and there were no curbs, only rubber-covered metal posts marking the boundary between car and pedestrian areas. As a driver, I found this design scary, because it was hard to visually see where I should be driving. But I noticed that t…

This is actually a fairly common redesign that one can find in several countries around the world over the past decade or so.

Re: Magic Roundabout (Swindon)

#194

Post by JdeBP »

dijit wrote: post #6

I grew up near a city called Birmingham in the UK which has it's share of... disturbing junctions: https://en.wikipedia.org/wiki/Five_Ways,_Birmingham https://en.wikipedia.org/wiki/Gravelly_Hill_Interchange They look insane on a map, they must have been hellish to navigate before GPS.

"Spaghetti Junction" was not. Just get in the correct lane, as signposted, and stay in it. It's actually easy to navigate. It may have resembled spaghetti to a headline writer in the 1960s, but it is not in fact a difficult junction.

Re: Magic Roundabout (Swindon)

#195

Post by JdeBP »

mabbo wrote: post #89
chrishannah wrote: post #18

That's not even the best "Magic Roundabout", the one in my town is much better! https://en.wikipedia.org/wiki/Magic_Roundabout_(Hemel_Hempst...

I'm Canadian. We had a work trip to the UK. My manager kept saying "I think I can handle driving in there, how bad could it be?". I told him we'd die. As we went through the Hemel Hempstead magic roundabout in the back of a cab, he turned to me and said "Okay... you might have been right."

As a Canadian, you should be proud that for almost 60 years you had a junction that was much worse, and possibly unique: the infamous Armdale Rotary, where traffic on the rotary and traffic joining the rotary alternated in priority.

* https://web.archive.org/web/20190816111546/https://en.wikipe...

Re: Magic Roundabout (Swindon)

#196

Post by jiveturkey »

frosted-flakes wrote: post #185
Sohcahtoa82 wrote: post #184

Earlier quoted context omitted.

> late merge asshole problem. Early mergers are the assholes. You're SUPPOSED to merge late. If you see a sign saying "Construction ahead 3 miles, left lane closed" or something, and you immediately start trying to merge, you're the one doing it wrong . Early merging creates unpredictability in traffic flow. Zipper merges are safer and lead to shorter merge queues. https://en.wikipedia.org/wiki/Merge_(traffic)#Zipper

There's a difference between late merges and late lane changes , which is what OP meant. When all vehicles are merging into one lane, sure, the zipper merge is superior. But when you realise you're in the wrong lane right before an intersection and try to force your way over, that's the problem.

Correct. I mis-spoke. I guess I picked up on 'late merge' term from someone else and that's how I call it. But indeed I meant a last-minute lane change.

Folks commenting on this, thanks for the correction but also you should have picked up from the context (of a tornado roundabout) that I was referring to a lane change.

Re: Magic Roundabout (Swindon)

#197

Post by dghughes »

burntoutfire wrote: post #68
dghughes wrote: post #55

Earlier quoted context omitted.

I don't understand how the turbo roundabout is any different than a typical two-lane roundabout. It looks like a regular two-lane roundabout from that picture in your link.

The difference is that, on a turbo roundabout, when you're on it, you're not allowed to go straight when on the right lane. Right lane is only for exiting the roundabout, while left lane is for either exiting or going forward to the next exit. This contrasts with the regular roundabout, where if you try to exit from the left lane, you are risking collision with someone on the right lane who's not exiting.

> This contrasts with the regular roundabout, where if you try to exit from the left lane, you are risking collision with someone on the right lane who's not exiting.

That's how the roundabouts are built where I am from. You can be in either lane and exit from the middle of outer lane. The right lane must exit the inner lane can go around or exit. Although some people in the outer lanes try to turn left and crash into the people in the inner lanes.

I get the difference now, that's how they should be here there would be fewer accidents.

Re: Magic Roundabout (Swindon)

#198

Post by mabbo »

Reason077 wrote: post #124
mabbo wrote: post #89

Earlier quoted context omitted.

I'm Canadian. We had a work trip to the UK. My manager kept saying "I think I can handle driving in there, how bad could it be?". I told him we'd die. As we went through the Hemel Hempstead magic roundabout in the back of a cab, he turned to me and said "Okay... you might have been right."

Statistically, you are less likely to die compared to driving in Canada. UK roads may be confusing, but they are significantly safer than Canadian roads, as measured by fatalities per billion km driven. (And Canada is already among the safest non-European countries, with significantly fewer fatalities compared to the USA)

This was years ago and I have actually now driven in the UK myself. Yes, I'm sure overall I'd be less likely to die if I were driving every day in the UK vs driving every day in Canada.

But let me tell you, the first day driving on the other side of the road is a real doozy. And I nearly died a couple of times. And I was doing my very best to avoid "magic roundabouts".

(I actually drove all week through rural Wales, which was a different kind of adventure)

Re: Magic Roundabout (Swindon)

#199

Post by TheCapn »

throw0101a wrote: post #183
TheCapn wrote: post #83

Earlier quoted context omitted.

RE: #2 Absolutely. Within Saskatchewan, east of Regina, we just completed three new bridges for suburban communities to access the main highway. In two of the three bridges were atypical designs using a Diverging Diamond at one point, and dual roundabouts at the other. When announced lots of people were fearful of the new designs and there was unsurprisingly a lot of outcry from ninnies who were afraid of the unknown…

> Within Saskatchewan, east of Regina ... Is it possible to get (Google?) Maps links for these?

Hi there, sorry about my delayed reply, I don't typically check comment replies on HackerNews. Doesn't look like Google's satellite has updated photos but here's some links:

The Diverging Diamond: https://www.google.com/maps/@50.4476864,-104.4361408,553m/da...

The Double-Roundabout: https://www.google.com/maps/@50.4769267,-104.2845914,552m/da...

The standard design: https://www.google.com/maps/@50.4471693,-104.3603897,781m/da...

Webpage of the project with some more info: https://www.reginabypass.ca/project/map-facts/

EDIT: If you drop yourself down into street view it looks like you can see how the designs are laid out. No satellite view yet though

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