8. Renwick Ruin
Even if a structure is already in ruins, it still might be worth protecting from future decay. While there are many landmark ruins across the globe, there is only one in New York City. That rare distinction goes to the Smallpox Hospital on Roosevelt Island known as the Renwick Ruin. The hospital was designed by noted architect James Renwick Jr. (who designed St. Patrick’s Cathedral) and was completed in 1856.
Around 7000 patients were treated for smallpox throughout the 19 years the hospital was open. The hospital closed in 1875 and services were transferred to North Brother Island. Renwick’s building was used as a training facility for nurses until 1950 when it then fell into a period of disrepair. Already in a state of decay by the 1970s, it was designated a landmark in 1976 for its “special character, special historical and aesthetic interest, and value as part of the development, heritage and cultural characteristics of New York City.”