Source: Adapted from Boeing, G (2019) “Urban spatial order: street network orientation, configuration, and entropy”. Applied Network Science 4, 67.
Note: Each city chart is a 360 degrees histogram divided into 36 bins. The length of each bin is the frequency of the streets having this bearing.
Since each street has two directions, each chart has a perfect 180° symmetry. Out of a sample of 100 cities, 49% have a general north-south-east-west orientation, with another 14% with similar orientations. Cities such as Chicago, Los Angeles, and Beijing show a remarkable consistency in the cardinal orientation of their streets. Even cities without a strong grid orientation often demonstrate an overall tendency to favor a north-south-east-west orientation.
Several cities on the above chart have a high level of entropy (disorder), such as Seoul, London, and Sao Paulo. This can result from a long history of successive urban developments, a complex landscape with hills and rivers, and a growth process that have annexed separate towns with their own street grids. Irrespective, cities worldwide depict a cardinal orientation.