Why the Bryant Park lawn has two hidden trap doors leading underground
Stand on the western edge of the Bryant Park lawn close to Sixth Avenue, and you’ll see a large rectangular plaque.
The plaque is a black and gold tribute to the donors who helped fund the renovation of Bryant Park, transforming what had been a sketchy patch of green in the 1980s to a Midtown gem flanked by office towers and the iconic flagship building of the New York Public Library.
But look closer at the wood platform the plaque sits on; it’s split into two. Turns out it’s not a traditional platform at all but two concealed doors. Where do they lead to?
These hiding-in-plain-sight doors open to a two-story, climate-controlled subterranean chamber built under Bryant Park for the New York Public Library’s enormous collection of books. It’s a book bunker of sorts, born of something most New Yorkers can relate to: a shortage of space.
Officially known as the Milstein Stacks, the subterranean space goes back to the 1980s. That’s when the New York Public Library flagship—which has graced Fifth Avenue on the eastern end of Bryant Park since 1911 (below, in 1915)—began running out of storage room.
Rather than ship extra books to a warehouse in New Jersey, the solution was to build underground stacks in a repository beneath Bryant Park.
First opened in 1991 and then expanded in the 2010s, the Milstein Stacks contain more than 55,000 square feet of storage space for roughly 2.5 million books and research materials, according to a 2017 article in publiclibrariesonline.org.
If you come upon the doors on the lawn, don’t attempt to open them and descend into the book bunker. The doors were not intended to be a main entrance. Rather, they’re trap doors staffers in the subterranean stacks can escape through in case of an underground emergency.
The stacks are accessible through the New York Public Library building, but “the vast underground nature of the facility means that in case of emergency, there had to be another way for employees to leave the Milstein Stacks,” explained an Atlas Obscura post. “Thus a large emergency hatch was built at the west end of the park, on the edge of the Great Lawn.”
Of course, an obvious set of doors on the lawn would attract a lot of attention and be catnip to urban explorers. So the doors were designed to blend in—hence the ordinary-looking plaque placed on top of them.
[Third image: NYPL Flagship Building in 1915; NYPL Digital Collections; fourth image: NYPL Flagship Building stacks under the building in 1911, from Scientific American; NYPL]
