A new geographical study of the United States reveals the functional boundaries of megapolises around the country, defining them by usage rather than arbitrary political borders. Unlike gerrymandered districts or state lines, these sprawling areas are rooted in deep data analytics versus historical accident.

Historical geographer Garrett Dash Nelson teamed up with urban analyst Alasdair Rae to publish a paper using commuting information and computational algorithms. Studying over 4,000,000 commutes, they traced interconnections between economically connected points and reported the results in An Economic Geography of the United States: From Commutes to Megaregions.

Taking it a step further, the authors also devised names for various megaregions extrapolated from the data – while semi-subjective, they start to give a sense of the real shape of metropolitan zones (and reveal areas where few residents and vast distances make it hard to define or confine regions).

Some cities at the heart of various sub-regions are not surprising — San Francisco and Los Angeles were givens — but others may be new to some people, like Fresno, California. Many cities trace influence across state borders, like Minneapolis into Wisconsin or New York City into effectively every adjacent state. Some overlap while others are isolated, especially in the west.

In the end, this is not a definitive way to look at geography within the Lower 48, but it does start to push the observer to rethink conventional regions of influence and defined borders. From the abstract: “The emergence in the United States of large-scale ‘megaregions’ centered on major metropolitan areas is a phenomenon often taken for granted in both scholarly studies and popular accounts of contemporary economic geography. We compare a method which uses a visual heuristic for understanding areal aggregation to a method which uses a computational partitioning algorithm, and we reflect upon the strengths and limitations of both. We discuss how choices about input parameters and scale of analysis can lead to different results, and stress the importance of comparing computational results with ‘common sense’ interpretations of geographic coherence.”

During the lead up to the invasion of Iraq, a German newspaper published step-by-step driving directions from Berlin to Baghdad, highlighting the interconnectivity of contiguous European and Middle Eastern land masses.

This series of maps from Moovel Lab highlights similar phenomena, starting with a map that shows the truth of an old aphorism about all roads leading to Rome. Ancient Romans created an estimated 50,000 miles of road across Europe, Asia and Africa, with their coastal Italian capital as the origin point.

Next, they moved on to 10 major cities in the United States, analyzing how regional traffic flowed into each, before going through a full analysis of fastest routes to state capitals. The results were surprisingly varied: “Remarkable are the different road networks throughout the States. While the east coast seems to rely on roads parallel to the coast. The rockies and appalachian mountains reveal their topography with their curvy roads containing some blank spots not reached by any road. While the mid west of the USA show long straight road networks in rectangular alignment.”

Their process is relatively intuitive. The mapmakers overlaid a grid on existing open-source maps, then added a query: how would one get from here to Rome (or other cities)? The results have been turned into maps that look almost like a study of the human vascular system, with small veins feeding larger arteries along the path to the hub point. “The outcome of this project is somewhere between information visualisation and data art, unveiling mobility and a very large scale. View and interactively explore all roads to rome and other cities.”