The abandoned New York islands that once quarantined the city's most dangerous diseases

Countries & Cities · Published 12 October 2026 Swipe more like this →

In short: Hidden in the East River between the Bronx and Rikers Island, the Brother Islands hold a haunting legacy. Once a site of medical isolation, these uninhabited outposts housed notorious figures like Typhoid Mary and served as a sanctuary for both war veterans and the city's refuse.

Originally claimed by the Dutch West India Company in 1614 as De Gesellen, these islands have undergone radical transformations. North Brother Island, spanning approximately 20 acres, became the site of Riverside Hospital in the mid-1880s. The facility was established to isolate patients from contagious diseases, including smallpox, typhoid, and tuberculosis. It even treated victims during the 1916 polio epidemic. The hospital's presence ended as medical advancements, such as the post-1945 availability of the tuberculosis vaccine, rendered large-scale quarantine obsolete.

The islands' history is marked by both tragedy and social upheaval. In 1904, the steamship General Slocum burned and beached on North Brother, resulting in 1,021 deaths. The islands also served as a place of confinement for Mary Mallon, known as Typhoid Mary, who lived there until her death in 1938 after being declared a public menace in 1915. Later, in the 1950s, the islands housed a center for adolescent drug addiction, a facility that eventually closed in 1963 following allegations of staff corruption and patient mistreatment.

Today, the islands are largely uninhabited and off-limits to the public, serving as a sanctuary for water birds like the double-crested cormorant and snowy egret. While many of the original 25 buildings on North Brother Island remain in extreme dilapidation, the islands were purchased by the federal government in 2007 and gifted to New York City. Despite various proposals by mayors like Ed Koch to repurpose the land, the islands remain a wild, decaying landscape, occasionally visited by researchers and journalists under strict supervision.

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