First, picture this. Instead of city roads being based around a grid, they are based around concentric circles of increasing radius. These circles are connected by straight roads that run radially out from the center most circle. I’ll call the circular roads, “circular roads”, and the straight roads, “radial roads”. The inside of the innermost circular road could be a park or town hall or something. There would probably be more radial roads the farther out you go, so that the distance between any neighboring radial roads doesn’t get to great.
My question is, what would the advantages and disadvantages of this system be, compared to the current grid road system.
NOTE: both the circular roads and the radial roads could be one-way, or not. Real cities use a mix of one-way and non-one-way roads, so how would one-way-ness affect anything?
bonus question
Getting from the northwest side to the northeast side would be cumbersome. The only advantage is if the center of town is truly a desirable destination for the majority of the population. Add in a sewage system that has to conform to a circular system, and I really can’t think of any positives for this system.
A handful of cities have some diagonal main streets to facilitate commuting from the corners to the center (DC, Indianapolis), but each of those are paired up with a fairly strict grid system as well.
Rectangular lots are easier to divide up evenly and build on. Using a circular grid would leave all sorts of odd-shaped property, some of which would be unsuitable for construction.
I’m pretty sure I’ve seen this done in history and the realisation was that a grid system is better - sorry no cites. BUT your question did get me thinking and I suggest a 6 (or more) lane spiral system, ONE WAY only. Imagine this, as you head into the CBD you start driving around town getting closer to the centre and when you reach the center, a BRIDGE takes you straight out. SHITTY DIAGRAM There will be no need for traffic lights, and there will be side parking on both sides. If you MISS your building/stop, the spiral will have “return roads” which will take you back to the last spiral… (no lights there either, only a give way sign)… The closeup on the right gives shows you that there will be 2 rows of building and each row facing the road.
OH… and pedestrians will take bridges or underground routes.
(upon preview) Reality Chuck… well, architects will just have to be more creative … lots dont have to be square for the building to be square.
Wikipedia has a good article about cities built on the Grid Plan.
I don’t know what term city planners use for the circular sort of design, but my town is built that way and I hate it. In a Grid Plan city, you can use any number of routes to get to your destination, as long as the east-west portions total the right distance and the north-south portions total the right distance, you can break them up however you like. But in a Radial Plan city, it is far too easy to make a mistake: The radial streets seem to be parallel but before you realize it you’re way off target; and the circular streets take you in… ummm… circles!
Anyway, if you want a good example of a city built circularly, use your favorite map program to look at Moscow.
FWIW, Washington, DC is sort of a blend of hubs with spokes and grids. No real concentric circles, though. It makes for sort of an interesting center at the spokes, but not great traffic flow and some weird driving once you get near the centers, if I remember. Biggest downside is that it’s confusing to newcomers, that is, it’s not intuitive how to use the system versus a grid.
I also find it’s much more intuitive to find addresses - even someone who’s never set foot in Manhattan before could find an address at “34th street and 5th avenue”. I think a circular system would be harder.
Either one is probably easier than the way we do it in Europe though - which is, no structure whatsoever. Have a look at a map of London. Even I get get confused all the time and I live there.
L’Enfant’s concern, when laying out D.C., wasn’t commuters – a category that didn’t exist at the time – but the military defense of the city, should it become necessary.
The original part of St. Louis is largely built that way. It’s a half-circle because the oiriginal downtown is right up against the river. But the basic *radials + circulars *pattern holds.
For between 5 & 15 miles out from downtown, the structure is major arterial roads are radials, and the major other-direction roads are circular. It isn’t the neat circles of Sun City, because a) the ground isn’t flat, and b) the layout just happened over 50+ years back in the late 1800s, it wasn’t bulldozed from fresh desert in a month.
Once you get a few miles out, there is usually a plain old grid stuck inside each wedge between the arterials. But the various grids are set up at diffrent angles to fit the space, so they meet at funny angles in a lot of places. And the ~1x1 mile area that is downtown downtown is also a grid.
How does all this work?
It works fine, although it takes some getting used to becasue a “northbound” road is rarely really pointed North. And as noted above, it is hard to travel cross-wise.
Nowadays, most people in the Greater St. Louis area live out in the plain old grid-like 'burbs and often work there too. But when you/they get down into the older parts, they get to deal with the weirdness.
Epcot, as originally envisioned by Walt Disney, would have employed circular streets. No traffic lights in the entire city. IMO, his vision was beyond practical for general use. The prototype was never built, I might be future-blind about it.
The town plan described by the OP is what I as an European would consider almost the default one - how a city develops that originates from an original walled town, once the walls are surplus to requirements and if no constraints of terrain or political geography force a non-radial outward development.
Of course that means that it’s a naturally developing pattern, not necessarily the ideal one. But in most cities the central resources (city hall, business/shopping district, main railway station &c.) are in the centre, so radial roads seem to have a point.
Yes, I was going to mention Canberra. Everyone complains about getting around Canberra, because you need to know at what point of the circular roads you need to get off. It’s a beautiful city (in part because it’s sustained by taxpayer dollars from the rest of Australia), and eventually you get used to driving in circles, but newcomers find it a paid to get around.
Detroit sorta had a radial plan. Gratiot, Van Dyke(see below), Woodward, Grand River, Michigan Avenue, and Fort radiate out from downtown. Van Dyke is slightly different; it’s straight north-south and does not radiate from nearly the same place as the others. I only include it because the angle between Gratiot and Woodward is comparatively large, and Van Dyke runs from deep in the city out beyond most suburbs. Those surface streets have largely been supplanted by a grid system though.
The major problem as I see it is that when you get to where the radial roads meet, there is a high density of roads and intersections. I was always confused when my father drove various places downtown, and he thought it was “easy” to explain as spokes on a wheel. Sure, it tells you the basic layout, but where all of them are coming together it’s massively confusing. I suppose it doesn’t help that as one gets closer to the river, the original French (from founding in 1701 to capture by the British in 1760) grid roads become aligned with the river instead of north-south like the later grid ones - and sometimes turn as the river turns.
Nevertheless, the freeways are basically radial, although the “circular” connectors are somewhat aligned to the grid. The former means getting downtown is quick from most anywhere in the inner to middle suburbs. The latter means that while it’s easy to go from northwest to either southwest or northeast, getting from northeast to southwest is a comparative pain. You either follow the grid of outer freeways or go all the way downtown.
There is one place where it is a pain getting downtown, and it’s that Van Dyke sector. Since it was a major arterial in the pre-freeway days, it’s relatively built up. There was a freeway built going north from 18 mile (ie, the major road 18 miles north of downtown), with plans to continue it along the parallel road a mile over (Mound). In the construction of I-696, a major e-w freeway around 11 mile, its intersection with Mound was built like a freeway interchange. However, it looks like it’ll never be built. At least I-75 comes within 4 miles of Van Dyke south of 16 mile.
