Like humans, cities and neighborhoods have their own unique fingerprints. While genes determine ours, a city’s mark is characterized by the relationship between buildings and open spaces. Think of it as “spatial DNA,” which is typically mapped out by urban designers and researchers in black-and-white diagrams. Black shapes indicate buildings and white represent the open ground.
“These are useful tools to [visualize] the micro-scale of urban [neighborhoods] and understand how buildings and their surroundings succeed or fail in making a continuous and integrated urban whole,” Peter Griffiths, editorial officer of the Cities Research Center at London School of Economics and Political Science, says in an email. The maps were created by researchers at the center’s Urban Age program, who have been studying how the layout of rapidly urbanizing cities can affect their livability. Researchers used satellite photography and official city data to create the maps.
They show that in some cities, like New York City, Lima, and Buenos Aires, neighborhoods are defined by grid-like patterns. In others, like London, the layout allows for more open spaces.
Within a city, layouts can differ greatly from neighborhood to neighborhood. In Rio de Janeiro, the difference in neighborhood density is largely a result of wealth distribution and formal versus informal settlements.
The most valuable visual information that these maps convey is the density of a particular area. Planned right, a dense city can be a positive environment for productivity. Griffiths explains that the clustering effect creates “agglomeration economies.” “If you cluster a whole lot of people close to each other, with skills that aren’t necessarily the same,” he says, “you get opportunities for new creations.”
But with dense cities comes challenges that can make them unsustainable, he adds: “You’ve got to put in decent public transport so that you can move people around the city, otherwise you get pollution and congestion.”
Griffiths says to think of a city like a market, where different people and services all come together. “You want to overcome the challenges of time and space by putting everything in the same place and making it quick to interact with other things,” he says. “That’s what cities do.”