This intriguing new visual maps the symmetry of urban layouts.
In a new set of data visualizations, Seth Kadish from Portland, Oregon, compares the street grids of two dozen urban centers across the U.S. and Europe.
The graphs, which plot the orientations of every road in a county or city, reveal just how much that region conforms to a street grid. In each graph, the tallest bar indicates the direction that more roads point to than any other direction. To ensure rotational symmetry in the graphs, each road is plotted to run in both directions, regardless of whether they're actually one-way or two-way.
As you can see below, Cook County, Illinois (Chicago) has a particularly pronounced grid. While San Francisco county has a strong grid, there's also a substantial number of streets oriented in all sorts of directions. For Manhattan, we see the dominance of horizontal streets over vertical avenues -- though as the graph shows, neither truly runs North-South or East-West. And European cities, not surprisingly, are far less orthogonal.
Detailed methodology and even higher-resolution versions of the graphics are available on Kadish’s website.
All images courtesy of Seth Kadish at Vizual Statistix.