The New York City subway system has 842 miles of track, making it the largest in North America. And there’s even more to it than riders see: dozens of tunnels and platforms that were either abandoned or were built but never used. They form a kind of ghost system that reveals how the city’s transit ambitions have been both realized and thwarted.

WNYC complies a map of abandoned subway stations and lines ( eleven in total) that were planned but never built. (Map by Balance Media / John Keefe/WNYC)