# Is it viable to build a city with a circle based architecture?

I know it may be impractical, but I have a culture who needs to build round structures for religious purposes.

I just wanted to know if it's feasible or if there are any deterrent factors or major reasons that it wouldn't work.

In the first image, the white circles are the houses and the dark grey ones are the streets with a circular park in the center. The second image shows the blocks, with circular gardens around some of them. Sorry about my drawing skills and I hope the pictures are intelligible. Thank you!

Edit: They have a medieval technology level.

• What do you mean by viable? In what sense? If it is possible from a pure engineering perspective or if cities in the (European) middle ages grew like that or if it has some severe drawbacks or something else? – Raditz_35 Feb 12 '18 at 16:51
• Would hexagons work? They naturally tessellate! – corsiKa Feb 12 '18 at 18:47
• A city full of roundabouts may actually be good for traffic flow. youtube.com/watch?v=HuKWHR5omU8 – Viktor Mellgren Feb 13 '18 at 10:02
• "for religious purposes. I just wanted to know if it's feasible" - Doesn't matter, it's religion. – DonQuiKong Feb 13 '18 at 16:11
• I love how if you want people to do something that makes no sense you can just invoke religion – Mikey Mouse Feb 13 '18 at 16:34

There are many benefits with having perfectly round buildings:

1. You minimize the cost of construction materials per interior area
2. You minimize the amount of wall space that are exposed to the elements for climate reasons (it's easier to heat a round room because there's less wall length for heat to escape. similarly, it's easier to keep a round room cool because you minimize the surface area that the sun can hit directly and warm the place up).

## Benefits

For reason 1, especially, your city's denizens might find it cheaper to build towers, that is to build up instead of building out. The citizens of your cities might find it more open to the public, as there are more empty areas around the buildings. Since this is medieval-level technology, it might make sense that instead of a park, instead the buildings are surrounded by a commons where goats and chickens can graze.

In addition, if there are indeed commons, it might make sense to erect fences to prevent each little commons' animals from escaping into the neighboring commons, and circles are really efficient for fencing. Finally, if your great city needs to be defended, its circular shape means that it is very efficient to create walls, and placing regular towers around the walls means that there are no blind spots to attack.

## Drawbacks

The biggest problem with your drawing is the lack of thoroughfares. There are no large, straight line of sight ways for people to travel across the city. Plus, there is no main promenade to parade your victorious armies through the streets, or to throw the annual religious procession. A sewer or aqueduct system would be inefficient to cover every citizen.

• @HansZ There's no reason the round buildings can't be laid out so there's a thoroughfare. You just have to be willing to pack them together a little less densely. Having straight main roads is not just convenient for ceremonial parades, but for giving directions. – Davislor Feb 12 '18 at 22:16
• @Scott star forts evolved during the age of gunpowder. Circular walls were preferred in ancient times because it let you wall in less area for the same amount of material. Additionally, there was less wall to cover so you could hold more area with a smaller force. – Hans Z Feb 12 '18 at 22:17
• I think this answer is missing one of the biggest issues: packing and space availability. Large cities grew up organically and if you build circles everywhere, there will be wasted space between them. Who owns the sudo-triangular gaps between them? If I can buy up part of the gaps, I could build a larger building in space in the shape of a hexagon (in reality they didn't all start with circles so they tiled with mostly rectangular shapes instead of hexagons.) – Shufflepants Feb 12 '18 at 22:50
• You forgot to mention in the benefits that a round building would have no corners and so it's the best shape for vacuuming! – Gábor Fekete Feb 13 '18 at 9:58
• no large, straight line of sight ways I would call this a benefit, because then the wind hasn't got free rein. In cities like Chicago the wind is a real issue exactly because of large straight lanes. – Pieter B Feb 13 '18 at 10:55

Having "round architecture" doesn't necessarily mean every building's floorplan is a circle.

The Round City of Bagdad is an example of high-level planning for a round city. The city was divided into four quarters by two perpendicularly intersecting streets that ran from end to end of the outer perimeter wall and terminating at four gates. Each of the four gates pointed towards a different city — Basra, Kufa, Khurasan and Damascus — and named after that. The gates opened onto an arcaded street running all around the exterior inhabited ring. The round city of Baghdad in the 10th century, the peak of the Abbasid Caliphate. Illustration: Jean Soutif/Science Photo Library

• Such a design needn't even be completely planned. The city Cologne has a pretty concentric layout as well, which mostly just evolved slowly over time – it being a pretty old city (ancient Roman) that never grew very fast so there aren't big rectangular patches, but it did keep growing over the centuries. Any extension would tend to try and keep close to the center, giving naturally a circular shape, and this was amplified by the desire to enclose as much as possible efficiently in walls. — But, is “single disc” what the OP was asking? – leftaroundabout Feb 13 '18 at 11:30

If you build it the way you have it in your drawings you would have a lot of wide open spaces between the clumps of buildings; plazas. Which is ok if that's what you want. Traffic would be a nightmare.

But if you built it more like this...

...you wouldn't get the open spaces (which might be wasteful) and you might get something that is more logical to people trying to find their way around (that's an aerial view of Burning Man by the way, look it up).

Most cities are all messed up in their lay out because different neighborhood's were built at different times. NYC's Manhattan is built as a grid because there is a finite space for it, an island.

But so long as your entire city was built all at once with a defined plan I don't see why you couldn't build it whichever way you wanted. I just think that any plan would want to take into consideration how logical it would be to its inhabitants.

EDIT: Your version could look like this:

• @Abigail the problem is that circles are very inefficient at using space because of the way they curve, curved rectangles are much better at utilising space. – Sarriesfan Feb 12 '18 at 18:33
• @Abigail I was offering this as an alternative to what the OP had in his diagrams. It still fits his circular need but would probably be more functional(?) – Len Feb 12 '18 at 18:50

### Yes - Denmark did it (kind of)

In Brøndbyvester (near Copenhagen), Denmark - there is a section of suburbs that looks very similar to your building plan.

(Note: I'm aware the buildings in this are still rectangular, but I'd write that down more to European convention which makes it cheaper to build. For your city, there's no reason cylindrical buildings could not be used. We have been successfully building round stone towers for hundreds of years without problems.)

The idea was to maximise the amount of open space and build small bundles of housing that are close together to give a small community feeling.

The solution to "what do you do with all the space in between the houses", is to use it for the population's benefit. In this case, it's open grass space to allow kids to play and people to walk dogs. Instead of looking at the tessellation as a problem - this area used it to force more open space than you'd normally get.

In your case, everything is scaled up so that the entire city is circular - rather than just a small neighbourhood. But the same idea could be applied, and would work so long as the city is build to a fixed plan. The key is not to see the empty space as a negative - but to find a use for it that would justify having a sparse city over a tight grid.

• +1 - nothing answers "can it be done" kind of questions quite as good as real life example that it was indeed done. – Mołot Feb 14 '18 at 15:10

The biggest drawbacks to cities like that is that they dont make very effecient use of space like squares do. In medieval times cities were built in a circular manner because they usually were all trying to huddle as close to a castles fortified walls as they could. Living close to a fortress refuge during a time of extreme uncertainty and violence outweighed the inefficient use of space and loss of productivity inherent in the design.

Circular cities also tend to run out of flat ground to expand across and begin developing haphazardly after that. Theres no reason your fictional culture CANT build that way if they wanted to, theyd just need A LOT of flat land to do it on. Also keep in mind theyd be wasting a TON of land for growing crops and stuff if "every single thing they build is circular" also includes farmland and property plots. If theres plenty of land and things are bountiful its not a problem, if theyre living in medieval european over-crowded conditions famines would probably become frequent enough to make them ignore circles and just use whatever land they could to grow food.

• Once you get modern irrigation technology, circular fields work quite well: hexagonal packing gets you about 91% utilization, and you can use center-pivot irrigation to water the fields. – Mark Feb 12 '18 at 21:53
• @Mark The only reason for the circular fields is that you can slowly, uniformly water it with a machine that spins around a center. The question specifically asks about a civilization at a level of tech equivalent to our middle ages. – Shufflepants Feb 12 '18 at 22:55
• Somewhat counterintuitively you can show that you can pack more circles of diameter D into a square than you can squares with sides of D, and oddly sized circles pack yet more efficiently than oddly sized (or angled) squares. There's definitely going to be space between the buildings, but whether it's wasted or not very much depends on your definition of waste. – Joe Bloggs Feb 13 '18 at 9:44

## Not too many problems when a building stands by itself

There are many examples (especially in indigenous cultures) with round/circular architecture. Saw this at the Met a while back: https://mymodernmet.com/round-home-architecture/ The walls of a structure do require a higher technological level, mostly because tree trunks grow straight—ergo, flat, wood walls are easy to build.

## Problematic with city planning, though

The difficulty I think you'd get with a city the way that you've shown it is that it's 1) inefficient for ushering trade through the city (I mean, who wants to walk/cart down a street that zigs all over the place and everywhere looks the same?!), and; 2) cities typical grow with different sections or quarters. However, I'm guessing the religious prohibitions maybe cover this.

• "Problematic with city planning" It's kinda the opposite of that. City planning would be the only way to do it. Because normally buildings and houses spring up around the already existing roads which were mostly straight because they didn't have any building to meander around. And if there's already a straight road in, you aren't just gonna start building your new house in the middle of that road. – Shufflepants Feb 12 '18 at 22:57
• @Shufflepants: That's what I meant. (What you affirm.) I agree. - DDM – user47438 Feb 13 '18 at 2:05
• Hi Daniel. All of your contributions are automatically attributed to your name with a link to your profile, so there's no need (and in fact strongly discouraged) to add a signature or tagline of your own. See What kind of behavior is expected of users? in the help center, particular the point on signatures. – a CVn Feb 13 '18 at 15:18

This reminds me of Jacque Fresco's The Venus Project, a futuristic city design. You can look it up: https://www.thevenusproject.com

Some examples:

It may not be exactly what you had in mind for design as not every structure is round, but in terms of viability it may help somewhat.

There is nothing that inherently makes this impossible but it is very unlikely.

1) Organization and planning. There were no building codes in the middle ages. You would have to have an organization that manages city planning. City planning was not unheard of in the middle ages but it was never this robust. You have a good start making it a religious requirement, but you would also need the governing power to be on board. Forcing this is going to cost the powers that be to enforce and implement.

Considering peasants made due with what was available to build their homes...well you are going to have to figure out how they are going to make peasants create things a certain way and whether are not they are going require standardized sizes and building materials.

2) Location is going to matter. A city on a plain could probably achieve this but in most cases in the medieval era you would not build on a wholly exposed plain. Its hard to defend. At a minimum you are probably going to need to deal with a coastline or a river. Medieval technology didn't allow city planners to alter the landscape like we can today. If you look at maps of ancient cities, Athens for example, you see that ancient cities followed the lay of the land.

3) Building round is fine. The technology required to build round is no major hindrance here. Its less efficient and more time consuming potentially but that's about all. Stone is going to be more difficult, but with wood you can set posts in place and then bend saplings in a circle. At that point the walls can be thatch or clay or mud brick or whatever, take your pick. There are plenty of examples of round dwellings from yurts to thatch.

4) Planning considerations. You should alter your city design to ensure transportation, communication, drainage and sanitation etc can be effectively managed. A spoke and wheel design allows you to be round and efficient. A design like this could serve you well.

Keep in mind the further from center you get the larger the distance you have to travel to hit one of the spokes. As such you are probably going to want more than 4.

• If round buildings had lasted into the planning permission age in the UK all buildings would now be required to be round, as new buildings have to match the general style of the area. – Separatrix Feb 13 '18 at 8:56

You might want to see the Koch Snowflake.

The main reason I recommend it is because two such snowflakes of different sizes can tesselate a plane. That is, completely fill the plane without any space left over.

The main problem with your circle idea is that even if you pack the circles as tightly as possible, you get a lot of leftover space. It's not so here.

You can keep the large ones as plazas and the small ones as houses, or the other way round, with medium-sized gateways enabling travel from one place to another. One of the main advantages is that every house is connected to three plazas.This also allows for straight travel, as opposed to the zigzag of your circle pattern.

• The gaps between buildings are important spaces, we don't want buildings to perfectly tessellate, we want roads to walk down. Round buildings are actually more efficient to move around between than more complex shapes. – Separatrix Feb 13 '18 at 8:54
• @Separatrix Which is why I recommended medium-sized gateways. with medium-sized gateways enabling travel from one place to another.  – MalayTheDynamo Feb 13 '18 at 15:46
• That seems a vastly overcomplex solution compared to just making the buildings round. The spaces between buildings tessellate perfectly with even irregularly shaped buildings. It's very pretty though. – Separatrix Feb 13 '18 at 15:52
• @Separatrix That it is. Though I assumed the OP would like strange shapes, because religion. – MalayTheDynamo Feb 13 '18 at 16:11

You might want to check out Ebenezer Howard and the Garden City movement, it might not be the best selling point for circular city planning though, no garden cities evolved into cities you'd recognize the name of. However, the main problem with Howard's idea, might not be the circular structure in itself but rather the anti-urban approach.

The popular wisdom (at this point in history) is that the main benefit of the city is density, It's a people and talent aggregator. People tended to meet in unexpected ways when they all were cramped in inside the city walls which lead to ideas meeting money (and so forth, you can check out Jane Jacobs for a bit more on urbanist ideas).

The exact shape of houses and public space is not extremely important, but there are some factors that you want to keep in mind in designing the city.

1) DENSITY: Stores, restaurants and other businesses all require a certain amount of potential customers to be viable. (This varies of course and factors such as customer segment, employee wage levels and rent levels at the location will guide what is sustainable at any given location.) This means you want not only people living close by but also the next point on the list.

2) COMMUNICATIONS: Urbanist (although not anti-urbanists or modernists) agree that the best locations for businesses are close to communication hubs and along thoroughfares. (Such as the main street.) You want fairly straight streets which cross through more than one neighbourhood. People who pass along from one place to another are the life blood of the city.

3) SECONDARY LOCATIONS: You can't just have major thoroughfares, those locations will quickly be filled with the business owners who can pay the premium prices (like real estate agents in major Swedish cities) and that will stifle creativity in your city. You want smaller streets and alleyways which connects the major streets. The spoked wheel city design suggested by James is a good start but also consider how the Burning Man site is laid out in Len's post. The grid pattern might not be the most practical use of space if all houses and quarters need to be circular, but you might want to give it a thought. How are people flowing in your city? Where do they go? How can their way be effectivized? The shortest path for the most people will be where the prime locations are. Radiating off from the prime locations will be the secondary locations.

The reason I bring this up is that we can see how cities who grew organically and gave space for these factors are the most successful cities. Cities planned according to modernist ideals about separation of function and city plans which looked great on a map (most famously Brasilia) tend to be very dependent on political power to stay afloat.

Which of course is another idea. A ceremonial political or religious city can be designed along totally different ideals. Maybe there is no need for commerce as we recognize it, the goods needed to sustain the perfect city is brought in and distributed to the elites from the outside. The only thing that matters inside is your social standing which is greater the closer you are to the center of the circle where the seat of power resides.

There are a number of deterrents and practical problems. The Dymaxion House design was a dome and commercial failure. The low cost didn't offset the aggravation of having no walls suitable for placing furniture along. In a medieval setting the interior layout would be further complicated by the large hearth and wooden chimney. You'd likely end up with a central fire which would really complicate interior walls. Japanese minka do feature a central fire venting through a thatched roof, but the rooms are along the exterior walls.

Construction itself is another potential challenge. Measuring the diagonals is a quick way to check rectangles for square, and when that's not practical larger right angles can be checked with a 3-4-5 triangle. Laying out a large circle is quite a bit more difficult in the middle ages. Domes and the Colosseum are ancient, but they were built by skilled craftsman. Many European homes were built by the owner, so you'd probably need more carpenters than history would suggest. (Especially with the added work bending wood. Or more masons if it's in stone.)

The real deal breaker is drainage. A bunch of round buildings aren't going to shed water in any consistent way, which means the entire base of the city would have to be graded. Alternatively, buildings would need to be on elevated areas between the streets. Having rainwater directed to the streets is fairly important when you consider that medieval cities had no organized street cleaning and most people emptied their chamber pots in the gutter. Residents of Paris were still wearing scented gloves in the 16th century to help with the stench.

Speaking of rain, a dome isn't a particularly brilliant choice of residence in any time when glass is a luxury. It's not like shutters would be particularly effective against water running down the wall. It's one more thing that's not a show stopper, but would probably require more specialized artisans depending on the climate.

Your city could be planned out like a honey comb, rather than a grid pattern.

• How would that be better? – Len Feb 12 '18 at 18:16
• A honeycomb is a grid pattern. Just not a rectangular grid pattern. – Logan R. Kearsley Feb 12 '18 at 18:24
• This was my thought as well, but it needs much more to be an answer. If I remember when I get home tonight I'll have a go if this is not fleshed out by then. – Mr.Mindor Feb 12 '18 at 18:25
• @Len It's better than circles because there is no/less wasted space between buildings. In big cities, no prime real-estate is wasted. – Shufflepants Feb 12 '18 at 22:53
• On the ground, once you have buildings of different sizes, a hexagonal grid is less efficient than a square one as it's much harder to have plots of varying sizes that tessellate nicely. – Separatrix Feb 13 '18 at 8:58

Round buildings are not a problem, and have certain advantages, and have in fact been built even with much less than medieval technology.

How to arrange such buildings makes a difference in how well the space around them can be used. Your examples of how to arrange them seem to me to have a lot of open space between clusters of houses that you say is "street" but is more like wide open spaces with little identical clusters of nine buildings. If the people like that specific pattern for religious or other reasons, ok, but it does use a lot of space and would be a unique experience and way to organize places.

I can imagine that a people could develop ways to relate to that pattern, if it's important to them, but it seems like a challenge compared to other patterns that might still use circular buildings and have circular layouts. In particular, leaving less space and arranging the groups so that there are more clear boulevards. For circular buildings of the same size. a honeycomb layout would be the most efficient use of space, and also lends itself to organized addresses. But you didn't really spell out what all of the religious rules are.

The size of a settlement also makes a big difference. Up to about the size of your first image, I could see people knowing where most people live and what most buildings are for, and just pointing and using a few words to tell someone where a particular building is, especially if there are background landmarks or colors or other ways to orient to which group of nine round buildings is which. But your second diagram looks like you're imagining a huge sprawling settlement that goes on and on repeating the same arrangement pattern, which seems to me like it could start to get quite challenging to keep track of (though I suppose if the culture and religion gave it a context that made sense, it might still be possible, perhaps something where there are epic mythological poems which correspond to the layout of the buildings, and could map to ways of getting between them - one could follow from place to place in story-reference order, if everyone knew the stories).

I would also consider that settlements don't generally appear all at once, but get built over time, and figure out how a pattern of building locations would grow as buildings are added.

Circular dwellings might make more efficient use of materials, if those materials are flexible, such as animal skins, thatch, etc.

But once you start using timber and brick, it takes much less skill and labor to cut or lay the materials in a straight line, store the materials for later, or provide thoroughfares.

• Your rectangular bricks have to be pretty big or the building pretty small before round walls become a problem. The bigger issue is that round buildings produce non square rooms which is bad for furniture, and reduce the surface area, which is bad for daylight. When living in a dome especially, you loose much of the efficiency gained by making it round to unusable space. – gunfulker Feb 14 '18 at 7:20