North Brother Island, located on the East River between the Bronx and Riker's Island, is an island with a fascinating and tragic history. It was uninhabited until 1885, when the city purchased the island in order to build Riverside Hospital, a hospital for people suffering from contagious diseases such as typhus, tuberculosis, yellow fever, and smallpox. The island's most famous resident was 'Typhoid' Mary Mallon, who was incarcerated there for over twenty years until she died in 1938. The hospital closed shortly afterward.

In 1905, over one thousand people lost their lives when the General Slocum steamship set ablaze near the island. Many of the staff assisted in the rescue of some of the 321 survivors. It was the worst loss of life in New York's history until the September 11, 2001, terrorist attacks.

The hospital was reopened after the Second World War, first to house war veterans and later as a treatment for heroin addicts. In 1963, it closed its doors for good and has been left to decay ever since. The island is officially off limits to the public, as it is a bird sanctuary for one of the area's largest nesting colonies of Black-crowned Night Herons.