Writer James Somers investigates why some train lines in New York City’s subway system do not have countdown clocks. The answers he found were at once unexpectedly complicated and predictably mundane: the system is so old that the technology that powers it is simply incapable of relaying such information, and the Metropolitan Transit Authority, which runs the system, is beset by bureaucracy.

But here’s the truly crazy thing: The only people who know exactly where that train is are on the train itself. The signal-tower operators don’t know; there’s no one in the Rail Control Center who could tell you, because the F isn’t hooked up to the Rail Control Center. Today, for the F train—along with the G, the A, B, C, D, E, J, M, N, Q, R, and Z—the best the system can say is that the train will get there when it gets there…

The best estimates today are that countdown clocks that tell you when the next train is coming will arrive on the so-called B division of the New York subway system in 2020. (The A division already has them.) That would make them about nine years overdue. It is easy to take for granted that governments move slowly, particularly on large infrastructure projects, particularly when those projects involve software. But we live in a world with cars that can drive themselves. Trains are huge objects that move in one dimension. How could it cost hundreds of millions of dollars and take nearly a decade just to figure out where they are and report that information to the public? Really: How?

Somers goes into some fascinating detail about how the early architects of the subway systems used archaic methods to ensure that trains never collide into one another, even though the system is essentially unaware of where any given train is at any given moment.

Read the full article at The Atlantic’s superb CityLab.