June Trotta, a banker from Brooklyn, was riding the uptown 5 train into Manhattan recently, and she was lost. The train stopped at Bowling Green, Trotta checked the map. The next stop was Fulton Street, and Trotta’s ears were beginning to turn red. “Oh no,” she said, turning to the woman next to her. “Why am I back where I started?” Trotta, a native New Yorker, doesn’t normally ride the 5. “I made myself get on it today,” she explained. “I’m trying to be a grownup about this.”

Four-point-seven million people ride the subway every day. Many of them are grownups, and many of them are lost. Among the eight largest underground rail systems: Berlin, Chicago, London, Madrid, Moscow, Paris, Tokyo, and New York, every city except for New York has a schematic map: a simplified diagram of the routes that run beneath the city, helping passengers get from point A to point B. The New York map, by contrast, is a mash up of underground lines and above ground geography, a dinosaur of design.