wnyc.org / 93.9fm / am 820

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.

MAP: Lost Subways: Abandoned Stations & Unbuilt Lines

Listeners weigh in on the "Koch Bridge" and "Carey Tunnel." Who would you name a bridge after? Henry Stern, director of New York Civic and a former city councilman and parks commissioner, joins the discussion.