North Brother Island is a small, deserted island in the East River, in the Bronx, New York City; it is just west of Rikers Island.
It and its smaller neighbor were named "Die Gesellen", or the Brothers, by Adrian Block, an agent for the Dutch West India Company.
It was unused and officially uninhabited for years. In 1885, Riverside Hospital, a sanitarium for quarantined patients, was moved there from Blackwells Island. Various other asylums, prisons, and hospitals were built there over the years, but fell into disuse.
In 1904, a steamship, the General Slocum, caught on fire and was beached on North Brother Island. Over 1000 passengers, mostly picnickers from a church, died in this disaster.
In the 1950's, Riverside became a drug rehab center. It was closed in 1963, and since then, the island has been deserted.
Note: there is also a North Brother Island in New Zealand. It is the home to a rare species of lizard, the Brothers Island tuatara.