Rory McCann's map reveals the locations of the world's straightest roads. (Map Credit: Rory McCann)

We may finally know where the world’s straightest roads run for miles on end, thanks to one man’s extensive research on the matter.

Rory McCann used mapping software OpenStreetMap (OSM) to that revealed straight roads primarily run through the Canadian prairies and American Midwest.

McCann’s theory on why this is the case is simple: American roads are straighter than European roads since they were built within the last 150 years, compared to European routes based on ancient roads.

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Much of the construction of the began in the 1900s, when the Federal-Aid Road Act of 1916 and Federal Highway Act of 1921 were passed, according to about.com Inventors.

Compare this to European roads, which were built as far back as the time in late 300 B.C., according to History.com

Looking around the globe, OSM measured a road’s “bendiness” ratio using the length of a road divided by the “straight line difference between its end points,” McCann said. He noted there is room for error, as the program is not yet complete.

In the map above, straight roads are displayed in a warmer color, whereas curvier roads are displayed in cool tones.

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