The Smallpox Hospital, sometimes referred to as the Renwick Smallpox Hospital and later the Maternity and Charity Hospital Training School, was a hospital located on Roosevelt Island in Manhattan, New York City. Originally designed by architect James Renwick Jr., the 100-bed hospital opened in 1856, when the area was known as Blackwell’s Island.[
Now in Ruins
A century after it opened, the hospital was closed, and the building eventually fell into disrepair. It was listed on the National Register of Historic Places in 1972 and designated a New York City Landmark four years later, the only ruin in the city with that designation. After the completion of an ongoing $4.5 million stabilization project, the Smallpox Hospital ruins will be open to the public. Source: Wikipedia.