Not so very long ago, New York Public Library buildings were heated by coal furnaces. Those furnaces required a lot of upkeep, and needed full-time custodians to look after them. That’s why New York City’s early library buildings also included apartments—they were designed as dwellings for on-site custodians and their families. But by the 1970s and ’80s, newer heating systems had replaced the coal-powered versions. Custodians retired and the apartments were left empty, some to decay and some to be renovated for new purposes. Today, only 13 of these original apartments remain.

In the video above, Atlas Obscura’s Sarah Laskow explores the secret apartment located in the Fort Washington library. To read more about these hidden apartments, read her feature story about them.

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