Transit-riding millennials are flocking to neighborhoods like Williamsburg, Bedford-Stuyvesant and Bushwick along the J/Z line in Brooklyn. The station at Flushing Avenue, for example, has seen ridership grow by almost 20 percent in just five years. But one thing hasn't changed: the entrance to the east — seen in the red dots below — has been closed for as long as anyone can remember.

Same for the entrances to the B/D/F/M trains at Broadway-Lafayette, on the southwest corner of Broadway and Houston in SoHo. Those account for just a couple of the 119 closed entrances across the system — remnants of brutal times for the city's transit system.

At its post-WWII peak, subways carried 6.9 million people each average weekday. But in 1976, ridership was about half of what it once was. Faced with declining revenues — and an increase in crime — the transit authority began closing entrances to save money and group riders together for safety-in-numbers.

But now ridership is once again approaching 6 million people a day. And those closed entrances are causing crowding, which in turn is causing delays. 

"You’re forcing people to enter at one or two access points," said Alan Minor, a board member of Neighbors Allied for Good Growth as well as a planning student at the Pratt Institute. People tend to congregate on the platforms near the stairways. And then, when it's time to get off the train, there are bottlenecks. Minor once timed the process at the Flushing Avenue station.

"It took almost two minutes for everyone to get off the platform," he said. "Which is to me insane."

The MTA knows the closed entrances are a problem. MTA spokesman Adam Lisberg said reopening them is "something we’re very actively looking at." But it will take time and money to figure out which of the 119 closed ones it's worth reopening.

In the meantime, some words of advice to riders: redistribute yourselves among the platforms, and have some patience when exiting.

Where are all the closed street entrances?

View full-screen map or embed it with this code.

Update: An earlier version of this map had certain stations in the wrong location.