Hypnotic Maps Show Most Popular Air Travel Hubs

Plotting the thousands of international air travel connections on a map sounds cool in theory, but all that data can quickly turn into one giant impermeable blob. Enter Swiss data visualization expert Martin Grandjean, who pulled off this feat without losing the threads.

His colorful, hypnotic maps don't merely show where everyone flies -- they also reveal trends.

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Grandjean decided to map the connections between all the airports worldwide as a "fascinating network visualization exercise," he wrote on his blog. Although that network is already technically a map, he pointed out that the dots representing airports usually end up being so dense that they're unintelligible.

In order to illuminate the actual network behind air transport, Grandjean used airport, airline, and route data from OpenFlights.org. He graphed 3,275 airports and 37,153 single routes -- weighted to 60,000 because many airlines take the same route -- and then applied a force-directed layout algorithm, which is basically a kind of aesthetically pleasing way to draw graphs.

Different colors represent longitude while the dot size corresponds with the number of routes. The result is surprisingly familiar looking. "The continents are mostly visible and regions are generally in their original position," he wrote online, although the Pacific Islands are an exception.

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This isn't the first time Grandjean has illuminated complex data. Last year he created a visualization about gun violence in America based on a New York Times article that had the stats. And this past April he mapped UNESCO's list of intangible cultural heritage elements to preserve, comparing them to World Heritage sites.

After examining his recent air traffic network visualization, produced with a tool called Gephi, Grandjean made several discoveries. He noticed that India is more connected to the Middle East than it is to either South Asia or East Asia. Latin America also appears clearly divided between a cluster in the south, and a Central American cluster closely connected to the United States.

Watch the world take flight in Grandjean's animated visualization here: