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The Irresistible Urge to Build Cities from Scratch

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Re: The Irresistible Urge to Build Cities from Scratch

#31

Earlier quoted context omitted.

In countries where they're common place and part of the licensing curriculum, roundabouts are far superior for throughput and traffic flow than any other kind of intersection of comparable size. To get any further improvement you start having to look at junctions with over head ramps and tunnels.

I think because the US only just started adding them, and various other intersection experiments, it will take us some time to become fully comfortable with them. My wife's family comes from a small town outside of a small town in Louisiana and I remember when they opened the traffic circle there [1], the entire town hated it because they had never in their lives had such bad traffic, because no one knew how to use a…

What you're describing is my experience with them as well. My parent's town in Ohio added one [1] and there was an uproar, but it's worked surprisingly well.

It replaced a very dangerous 4 way stop/traffic light intersection that very regularly saw accidents due to the geography (hilly) and the road layout (straight into the intersection after a mile of rural road).

1 - https://goo.gl/maps/NmyMpNEqn8A2

Re: The Irresistible Urge to Build Cities from Scratch

#32
post #19

Earlier quoted context omitted.

Cul-de-sacs decrease criminality too. If you go down a cul-de-sacs to do recon, you look out of place.

The Wikipedia page has several paragraphs on "this disputed issue", describing both pro- and con- views. One cited paper concludes "relative affluence and the number of neighbours has a greater effect than either being on a cul-de-sac or being on a through street".

so if living on a cul-de-sac predicts for relative affluence, it may be a proxy for lower crime?

Re: The Irresistible Urge to Build Cities from Scratch

#33

Earlier quoted context omitted.

We have a few roundabouts in my town in SoCal, small ones, and they all have stop signs.

That's kind of stupid...takes the point away from roundabouts. They're designed to keep the traffic flowing in low /medium conditions when a traffic light or stop sign would bring it to a halt otherwise. Saves on fuel etc.

You have no idea how frustrated they make me.

Re: The Irresistible Urge to Build Cities from Scratch

#34

I'm a huge fan of the winding maze like structure of cities built upon the old. It's nice to be able to wander and explore. I suppose blank slate cities (like most in America) are a lot more convenient to navigate though.

All cities started as a blank slate.

Recent US cities grew very quickly in a rather organised way and a grid was the quick and simple way to handle that.

Re: The Irresistible Urge to Build Cities from Scratch

#35
post #34

I'm a huge fan of the winding maze like structure of cities built upon the old. It's nice to be able to wander and explore. I suppose blank slate cities (like most in America) are a lot more convenient to navigate though.

All cities started as a blank slate. Recent US cities grew very quickly in a rather organised way and a grid was the quick and simple way to handle that.

> All cities started as a blank slate.

Not at all, many cities evolved from towns, that evolved from villages, that evolved settlements, etc. That slow organic growth is different from the very accelerated "add one more tile" or "do it in one go" growth.

Imagine the difference between having a baby that grows into an adult, and having an adult from the get go.

Re: The Irresistible Urge to Build Cities from Scratch

#36
post #13

Earlier quoted context omitted.

Diagonals can be okay used sparingly, but roundabouts destroy traffic flow the way Americans do them (with lights).

As an American, I detest roundabouts. I've never encountered one with a light before.

Why do you hate them?

Re: The Irresistible Urge to Build Cities from Scratch

#37
post #35
post #34

Earlier quoted context omitted.

All cities started as a blank slate. Recent US cities grew very quickly in a rather organised way and a grid was the quick and simple way to handle that.

> All cities started as a blank slate. Not at all, many cities evolved from towns, that evolved from villages, that evolved settlements, etc. That slow organic growth is different from the very accelerated "add one more tile" or "do it in one go" growth. Imagine the difference between having a baby that grows into an adult, and having an adult from the get go.

At one point there was nothing where every single city now stands. Everywhere it started with a blank slate.

The difference is the speed of development and, even more importantly, the level of planning.

US cities grew quickly and were planned.

Some modern cities that grew very quickly recently are nevertheless messy because they grew without any sort of planning.

Some cities are quite old but nevertheless follow a grid because that's the way they were planned. E.g. Beijing.

Planning is the key.

Re: The Irresistible Urge to Build Cities from Scratch

#38
post #19

Earlier quoted context omitted.

The Wikipedia page has several paragraphs on "this disputed issue", describing both pro- and con- views. One cited paper concludes "relative affluence and the number of neighbours has a greater effect than either being on a cul-de-sac or being on a through street".

so if living on a cul-de-sac predicts for relative affluence, it may be a proxy for lower crime?

... no? At least, that's not what I inferred from the Wikipedia article.

If you want to dig into the details, the report is at https://spacesyntax.com/wp-content/uploads/2011/11/Hillier-S... . A quick search finds the following in the conclusion section:

> Cul de sacs or grids?

> The principle that larger the numbers of dwellings on the street segment reduces the risk of burglary, applies both to cul de sacs and grid like layouts. Small number of dwellings in a cul de sac are vulnerable, especially if the dwelling are affluent.

Re: The Irresistible Urge to Build Cities from Scratch

#40
post #13

Earlier quoted context omitted.

Diagonals can be okay used sparingly, but roundabouts destroy traffic flow the way Americans do them (with lights).

As an American, I detest roundabouts. I've never encountered one with a light before.

Roundabouts are simple to navigate. You simply go around them.
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