The practice of separating homes, businesses, and factories into their own dedicated districts is called "Euclidean zoning." Given that Euclidean zoning involves the slicing and dicing of city maps into color-coded districts, you might assume it is named after Euclid, the ancient Greek "father of geometry" who laid down the rules for drawing lines and shapes on flat planes. But if you ask an urban planner, he will tell you that Euclidean zoning is actually named after a town in Ohio.
In 1922, Euclid, Ohio, passed a comprehensive zoning code to protect its small-town character from expanding, industrial Cleveland next door. The code drew the ire of the Ambler Realty Company, which objected to the town's imposition of a residential-only zone on a piece of land it had hoped to use for industrial development.
