The “Don’t Honk” signs came down a few years ago. Notices urging pet owners to clean up after their dogs disappeared from New York City streets not long after.

Now, another directive posted in the city’s public spaces is being removed: where to wait for a subway train late at night.

That such instructions even exist is news to many.

“I never even noticed it,” Eddie Rodriguez said as he stared at a large yellow sign that read “Off hours waiting area” in the Astor Place subway station in Manhattan.

“What does that even mean?” he asked.

Mr. Rodriguez, a New York native who rides the subway every day, is not alone in his confusion. Although still valued by some, the designated waiting areas — well-lit spots within eyeshot of a station agent or next to an intercom — are unknown to many riders today. They will soon become even more obscure.