Where are the world's largest cities?

An astronaut's eye view of urbanisation. Image: Getty.

Every year or so, Demographia, the St. Louis-based consultancy, publishes the World Urban Areas Report – a sort of bumper book of city population stats.

The report is a veritable treasure trove of demographic stats for city nerds. If you want to know whether, say, Edinburgh is one of the 1,000 biggest cities in the world, then Demographia will tell you. (It's not, it's just outside at joint 1017th). And if you want to know whether Paris covers a bigger land area than London, it'll tell you that, too. (It does: 2,845km2, as opposed to 1,738 km2.)

It even includes estimates for the size and density of hundreds of towns so tiny that you're slightly surprised to find that anyone on the other side of the Atlantic has even noticed they exist. (Favourite example: Kidderminster*.)

But the most fun is to be found in the first half of the report. Table 1 includes the 1,022 built-up areas in the world that house 500,000 people or more, ranked in order of population; Table 2 ranks the same cities in order of land area.

I don’t know about you guys, but we are stoked.

via GIPHY

(*55,000 people in 16 km2, giving a population density of 3,400 per km2, since you ask.)

Understanding the numbers

Explanations first. The report defines urban areas as

...a continuously built up land mass of urban development that is within a labour market (metropolitan area or metropolitan region)... [and] contains no rural land.

We should probably also note the reports caveat, about the limits of its own methodology:

Revisions are made as more accurate satellite photographs and population estimates become available. As a result, Demographia World Urban Areas is not intended for trend analysis.

Year-to-year changes indicated in population and land area may merely reflect better data that was not used before and may not, therefore indicate a trend.

In other words, if this year's report has a larger estimate for a city's population than last year's report, that might mean the city has grown. Then again, it might just mean that new, more accurate data has appeared.

Moreover, nearly all of the data is estimated. Appropriate caution is therefore advised.

Spoilsports.

The biggest cities, by counting people

Anyway, let’s get to the fun bit. Here are the 10 largest cities in the world by population:

It’s pretty familiar stuff. The top 10 is dominated by Asian cities, with a strong showing from New York City. Tokyo is far in the lead, with Jakarta and Delhi coming up behind. For anyone who pays any attention to this stuff, there aren't at first glance any massive surprises.

We're not supposed to compare with last year's figures for all the reasons laid out above, but what the hell, here's the 2015 top 10:

There are two big differences worth noting. One is that only one Chinese city is now in the top 10, down from three last year. (Beijing and Guangzhou are now ranked 11th and 13th.) All three have seen their populations revised downwards: this seems to the result of previous over-estimates, rather than mass evacuations.

The other noteworthy trend is the sudden appearance in the top 10 of Mumbai, with nearly 23m people. Last year, it ranked 13th with 17.7m. In a section headed "Revised data: highlights", the report notes:

The Mumbai built-up urban area has been expanded to incorporate the Bhiwandi, Kalyan and Vasai-Virar urban areas.

In other words, it isn't that a population the size of Madrid has moved to Mumbai over the last year. Rather, it's become clearer that the megacity has expanded to swallow surrounding areas.

You can see why ranking cities is a complicated business.

The biggest cities, by measuring land

As noted, most of the biggest cities in the world by population are in Asia. Most of the biggest cities in the world by physical size are, well, somewhere else.

Suddenly, with the single exception of Tokyo, Asia doesn’t even feature. Eight out of 10 are in the US. Atlanta has an estimated 5.1m residents, so measured by population it’s the 79th largest city in the world. Measured by land area, though, it ranks fourth.


I guess this is what happens when you build your cities around the car.

Incidentally, the report estimates Atlanta's population density to be 700 people per km2. The comparable figure for Dhaka in Bangladesh – 16.2m people, the 16th largest city in the world - is 44,100.

Dhaka is 63 times more crowded than Atlanta.

All the megacities

One more chart: this is the top 36 by population.

The reason we've stopped at that arbitrary point is not to get London into the rankings (well, not only for that reason). It's because the common definition of megacity is that with a population over 10m.

This is all of them. We've colour coded them by continent:

That's three each in North America, South America, Europe and Africa.

But the remaining 24 – two thirds of all the world's megacities – are in Asia. Five of them are in China alone.

Here, because we love you, is the data used in that graph. Enjoy.



Rank City Population
1 Tokyo-Yokohama 37,750,000
2 Jakarta 31,320,000
3 Delhi 25,735,000
4 Seoul-Incheon 23,575,000
5 Manila 22,930,000
6 Mumbai 22,885,000
7 Karachi 22,825,000
8 Shanghai 22,685,000
9 New York City 20,685,000
10 Sao Paulo 20,605,000
11 Beijing 20,390,000
12 MexicoCity 20,230,000
13 Guangzhou-Foshan 18,760,000
14 Osaka-Kobe-Kyoto 16,985,000
15 Moscow 16,570,000
16 Dhaka 16,235,000
17 Cairo 15,910,000
18 Bangkok 15,315,000
19 Los Angeles 15,135,000
20 Kolkata 14,810,000
21 Buenos Aires 14,280,000
22 Tehran 13,670,000
23 Istanbul 13,520,000
24 Lagos 12,830,000
25 Shenzhen 12,240,000
26 Rio de Janeiro 11,815,000
27 Kinshasa 11,380,000
28 Tianjin 11,260,000
29 Lima 10,950,000
30 Paris 10,870,000
31 Chengdu 10,680,000
32 Lahore 10,355,000
33 London 10,350,000
34 Bangalore 10,165,000
35 Ho Chi Minh City 10,075,000
36 Nagoya 10,035,000

 

And if you want more of this stuff, here’s our report on the 2015 edition of the Demographia World Urban Areas Atlas.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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Here’s how Henry Ford and IKEA could provide the key to solving the housing crisis

A flatpack house designed by architectural firm Rogers Stirk Harbour and Partners, on display at the Royal Academy, London, in 2013. Image: Getty.

For many people, the housing market is not a welcoming place. The rungs of the property ladder seem to get further and further out of reach. There are loud calls to build hundreds of thousands of new homes (and equally loud demands that they’re not built in anyone’s back yard).

If there was ever a time to introduce mass-produced affordable housing, surely that time is now.

The benefits of mass production have been well known since Henry Ford’s car factories made the Model T back in 1908. It was only made in one colour, black, for economic reasons. Not because it was the cheapest colour of paint, but because it was the colour that dried the quickest.

This allowed the production line to operate at faster, more cost effective, speeds. And ultimately, it meant the product could be sold at a more attractive cost to the customer.

This approach, where processes are tested to achieve increasingly efficient production costs, is yet to filter properly into the construction of houses. This makes sense in a way, as not everybody wants exactly the same type of house.

Historically, affordable mass-produced housing removed a large amount of customisations, to ensure final costs were controlled. But there is another way. Builders and architects have the ability to create housing that allows a level of flexibility and customisation, yet also achieves the goal of affordability.


Back in 2006, the “BoKlok” approach to affordable housing was launched to great acclaim in the UK. Literally translated from Swedish, the term means “live smart”. Originally created from a collaboration between flat-pack favourite IKEA and Swedish construction giant Skanska, the BoKlok housing approach was to allow for selected customisation to maximise individuality and choice for the customers. But at the same time, it ensured that larger house building components were duplicated or mass-produced, to bring down the overall costs.

Standard elements – wall panels, doors, windows – were made in large numbers to bring the elemental costs down. This approach ensured the costs were controlled from the initial sketch ideas through to the final design choices offered to the customers. The kitchens and bathrooms were designed to be flexible in terms of adding additional units. Draw and cupboard fronts interchangeable. Small options that provided flexibility, but did not impact on overall affordability.

It’s a simple approach that has worked very well. More than 10,000 BoKlok houses have now been built, mainly in Norway, Sweden and Denmark, with a small number in the UK.

But it is only part of the architectural equation. The affordable housing market is vital, but the cost of making these homes more adaptable is rarely considered.

Flexibility is key. The needs of a house’s inhabitants change. Families can grow (and shrink) and require more room, so the costs of moving house reappear. One clever response to this, in BoKlok homes, has been to allow “built in” flexibility.

Loft living

This flexibility could include a loft space that already has flooring and a built in cupboard on a lower floor which can be simply dismantled and replaced with a “flat-pack style” staircase that can be purchased and installed with minimal disruption to the existing fabric.

Weeks of builders removing walls, plastering and upheaval are replaced by a trip to the IKEA store to purchase the staircase and the booking of a subcontractor to fit it. The original design accounted for this “future option” and is built into the core of the house.

The best approach to new affordable housing should consider combinations of factors that look at design, materials and processes that have yet to be widely used in the affordable housing market.

And the construction sector needs to look over its shoulder at other market places – especially the one that Henry Ford dominated over a century ago. Today’s car manufacturers offer customised options in everything from colour to wheel size, interior gadgets to different kinds of headlamp. These options have all been accounted for in the construction and costing of each model.

The ConversationThey share a similar design “platform”, and by doing so, considerably reduce the overall cost of the base model. The benefit is quicker production with the added benefit of a cost model that allows for customisation to be included. It is a method the construction sector should adopt to produce housing where quality and affordability live happily together.

David Morton, Associate Professor in Architecture and Built Environment, Northumbria University, Newcastle.

This article was originally published on The Conversation. Read the original article.