New York’s Treasure Trove of Tiny Islands

Rat Island as seen from City Island in the Bronx. The tiny patch of land sold to Alex Schibli, a Bronxite, for $160,000. Wikimedia/Stercus.caput

How many islands make up New York City? As a proud daughter of the Empire State, with family roots going back centuries, I didn’t know the answer. I am a former Queen of the Coney Island Mermaid Parade, a card-carrying member of the Coney Island Polar Bears and my Uncle Joe was a tugboat captain. I should know this. I kayak in the mighty Hudson River, my great-grandfather owned garbage barges…Really, there’s no excuse.

Four of our five boroughs are islands or are connected to an island. Think about it: We have Manhattan Island and Staten Island, and then Queens and Brooklyn are both located on Long Island. The Bronx is the only borough that is connected to the mainland of New York State. The name Manhattan has been traced to the Munsee words “manahactanienk,” which either means “place of general inebriation” or “Menatay” meaning “Island of the Hills.”

In “Leaves of Grass,” Walt Whitman exclaimed: “The beautiful city, the city of hurried and sparkling waters! The city of spires and masts! The city nested in bays! My city!”

This week’s sale of Rat Island, a rocky two acres in City Island Harbor in the Bronx, ignited my curiosity about our city of islands. Alex Schibli, a retired Port Authority worker was the winning bid at $160,000.  Schibli intends to keep the island as it is; he believes it should be conserved in its natural state.

In tribute to the honor and integrity of Schibli, here is a brief overview of the islands of New York City.

Our city is located in one of the world’s largest natural harbors, with 578 miles of waterfront. Several of our islands are home to millions of people; several have historical significance, such as Ellis and Liberty Island. Some Islands were used to quarantine patients during epidemics, like North Brother Island, Swinburne Island and Schibli’s new real estate, Rat Island. Others serve as penal colonies, like Rikers Island, while others were the base for rendering plants and fertilizer factories, like Barren Island, where it was said the stench could be carried on the wind for two miles. One island is the resting place for over 850,000 souls, a potter’s field on Hart Island.  One of the smallest is 100 feet by 200 feet and is named in honor of the third secretary general of the United Nations, U Thant Island.

So, how many islands make up the archipelago of New York City?  The answer is, it depends on the tide. When the tide is low, smaller islands and islets like Pumpkin Patch Marsh or The Cuban Ledge are visible. At high tide, they are under water.  A few islands have been connected to larger islands with landfill.  There are between 36 and 42 islands, according to “The Other Islands of New York City,” by Stuart Miller and Sharon Seitz.

Mayor Michael Bloomberg stated: “New York City’s smaller islands are our secret treasures.” Here are a few of our other treasured islands:

Hart Island

Hart Island, pictured on lower right, is near City Island in the Bronx. A potter's field on the island contains the remains of over 850,000 unidentified persons and is tended by inmates from Rikers Island. Flickr/dsearls

Hart Island, located in the Long Island Sound just north of City Island in the Bronx, is the site of the largest tax funded cemetery in the world — the potter’s field for New York City. Since 1869 more than 850 thousand people are interred in three unmarked gravesites. All of them unclaimed and most of them unidentified. A large granite cross was erected in 1902 with the inscription, “He calleth his children by name.” Prisoners from Riker’s Island volunteer for the detail to bury the dead. The only access is via a ferry, which is operated by the Department of Corrections. There are no provisions to visit Hart’s Island without communicating with the Prison System. Press is not allowed.

North Brother Island

North Brother Island is located in the East River and has a neighboring island called South Brother Island. It was privately owned but was purchased by the city in 1871. In 1885, Riverside Hospital was built to treat patients with infectious diseases. One of the most well-known patients was Mary Mallon, also known as “Typhoid Mary.” She was a cook in a prosperous household and was first recognized as a carrier of Typhoid fever when there was an outbreak at her employer’s house in 1904. She was quarantined at Riverside Hospital from 1907 until 1910. A brief release during which she continued to work as cook despite her vow not to ended in 1915, when she was again institutionalized at Riverside Hospital and spent the remainder of her life quarantined on North Brother. All told, she was implicated with causing 47 cases of typhoid fever and three deaths.


North Brother Island was originally the site of Riverside Hospital. It was later converted to GI housing after WWII and then abandoned by 1963. Today, North Brother Island is a protected heron habitat, owned by the Department of Parks and Recreation. Video produced by Daniel Ross and Bijan Rezvani.

North Brother Island was also the location where the excursion vessel “General Slocum” ran aground after it caught on fire in June 1904.  The fire was the worst single disaster in the history of New York City until the attacks on the World Trade Center. It was one of the worst disasters in maritime history. At least 1,021 people, mainly women and children, died near the shores of North Brother Island.

U Thant Island

At a mere 100 by 200 feet, U Thant Island is New York Harbor's smallest island. A time capsule on the island contains the personal effects of U Thant, the third secretary general of the U.N. Photo courtesy of Wikimedia. This image is in the public domain.

Here is an Island just for U. U Thant is the smallest of the Manhattan islands. It is a manmade islet measuring 100 feet by 200 feet. The island is located in the East River, South of Roosevelt Island, midway between the United Nations and Long Island City. A council of U.N. Employees called the Peace Meditation leased the Islet from the State of New York and unofficially named it after the third secretary general of the U.N., U Thant.  Thant was a devout Buddhist and on U Thant Island you will find a “oneness arch,” a time capsule of U Thants personal items which was dedicated in 1977.

Karen Duffy, “Duff,”  is an eighth-generation New Yorker, amateur historian, model, actor, bestselling author and journalist.

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