Libraries are places of wonder that inspire and satisfy the inquiries of curious minds, and there are very few libraries that do so better than the New York Public Library’s Stephen A. Schwarzman Building. Standing proudly between Fifth Avenue and Bryant Park, the New York Public Library‘s midtown branch, often referred to as the “main branch” of the city’s public library system, is an invaluable research resource, an architectural treasure, and a historic New York City institution.

The New York Public Library (NYPL) was founded in 1895 when already established library institutions created by John Jacob Astor and James Lenox were combined, along with a fund created by Samuel J. Tilden, to create the new free and public library system. The building that would house this new library was designed by the renowned architecture duo of Carrère and Hastings. The library was officially dedicated on May 23, 1911, sixteen years after the historic agreement between Lenox and Astor.

Now, more than 100 years later, the library continues to serve the intellectual needs of New Yorkers, expanding to 92 locations and four research centers systemwide. The original midtown library building, now considered the main branch of the system, is the second largest library in the world, just behind the Library of Congress in Washington, D.C, and one of the largest in the world. Within its walls the library holds not only millions of books and priceless artifacts, but also many secrets waiting to be discovered.

The New York Public Library is one of our partners for the Untapped Cities Insiders program, offering off-limits access on Insiders visits to their branches and archives. The group will be headed next to discover the NYPL Library of the Performing Arts. Read on to find out the top 10 secrets of the New York Public Library:

1. You Can See Remnants of the Old Croton Reservoir Inside the Stephen A. Schwarzman Building


Getting fresh and clean water to New York City was a major challenge in the early 19th century as the city rapidly expanded. The solution to the city’s water needs was the Old Croton Aqueduct. Construction started on this water transportation system in 1837 and water first flowed through it in 1842. The aqueduct moved water from the Croton River in upper Westchester county down into Manhattan. The water was stored in a receiving reservoir which was located where the Great Lawn of Central Park is now, and was distributed from a reservoir at the current site of the Schwarzman building. That reservoir was known as the Croton Reservoir.

The Croton Reservoir held 20 million gallons of water within its walls which stood 50-feet tall and 25-feet wide. Edgar Allan Poe frequently walked atop the reservoir walls to enjoy the view they offered of the city. When it became obsolete in the 1890s, it was torn down to make way for the new library building. It took two years and some 500 workers to dismantle the reservoir. The cornerstone of the library was laid in 1902. The Old Croton Aqueduct would serve as a vital water supply for New York City for nearly a century until a new aqueduct was built which remains in service to this day. Inside the library, you can still see pieces of the reservoir walls if you look for the rough stone between the stairs on the lower levels of the South Court, near the Celeste Auditorium.