Opened in 1856, this smallpox hospital on the southern tip of Blackwell's Island (now Roosevelt Island) was part of a multitude of public institutions to care for New York City's unfortunate and destitute. The island sits between Queens and Manhattan, and was easily accessible by ferry; it was home to a prison, insane asylum, and other similar facilities. The remote location made this a prime location for the care of victims of smallpox, although both charity cases and paying patrons were admitted.
The 100 bed facility was designed by architect James Renwick Jr., whose more notable works include St. Patrick's Cathedral and Grace Church. The lower floors were used for charity cases and the paying inpatients were kept in private rooms on the upper floors. The original structure measured 354 x 122 ft., and was divided into 29 wards, the smallest of which contained 13 beds and the largest 39. As of 1872, an annual number of 7,000 patients were treated, with an average of 450 deaths. It was first administered by the Commission of Charities and Correction, but was transferred to the Board of Health in 1875, where it changed roles due to both the treatment of smallpox and other contagious diseases being administered in facilities on North Brother Island, as well as reducing the risk of spreading the disease throughout the population of Blackwell's Island, which had grown significantly since its initial construction.
The imposing gothic structure was emptied of patients in 1886, and was used both as a nurses home as well as The Maternity and Charity Hospital Training School (Charity Hospital was located just north of Renwick, later known as City Hospital). Two wings were added to the original block with a similar design: the south wing in 1903-1904 and the north wing in 1904-1905. The island was renamed Welfare Island in 1921, and in the 1950s many of the institutions on the island became obsolete and were abandoned, including City Hospital which had moved to Queens, and its nurse's quarters, Renwick Hospital.
Welfare Island was renamed once again to Roosevelt Island in 1973, and during this time Renwick fell into ruin quickly even though it was deemed a historic landmark worthy of preserving. A preservation effort was attempted in 1975 under the direction of architect Giorgio Cavaglieri to help preserve the exterior facade, but no other attempts were made to save the building from collapse and decay.
Only the gray gneiss and brick foundation remain; no roof, no inner walls, and barely any floors. Wooden timbers support the balconies from the 1975 preservation effort, as well as some rickety scaffolding inside the foyer. It is now behind a fence, and has been designated a national historic landmark. In 2009, Four Freedoms Park was built on the southern tip, and includes a $4.5 million stabilization plan for the hospital to open it to the public.
More information can be found at Roosevelt Island Historical Society.