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The islands you've never heard of -

City Island and Hart Island are the largest of the Pelham Islands, found in the New York City borough of the Bronx. Between them are The Blauzes and Chimney Sweeps Islands—just a few of the city's often overlooked islands. But there are many more...

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Hart Island -

Located at the western end of Long Island Sound, Hart Island has in its time been the location of a prison camp, a psychiatric institution, and a tuberculosis sanatorium. Its potter's field (a place for the burial of the unknown) has existed since the American Civil War. Recently, those buried on the island have been victims of COVID-19. Mass graves have been dug to accommodate the influx of dead during the coronavirus pandemic.

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Hart Island -

Actually, more than one million dead have been buried on the island since the 19th century. Graves have been traditionally dug by inmates from Rikers Island correctional facility. Hart Island today is a forlorn and dilapidated destination. The island was intermittently used as a prison and a homeless shelter until 1967, and the last inhabited structures were abandoned in 1977. Only the graveyards remain.

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Randalls and Wards Islands -

Randalls Island and Wards Islands are two conjoined islands separated from most of Manhattan by the Harlem River, from Queens by the East River and Hell Gate, and from the Bronx by the Bronx Kill. Most of the destination is parkland featuring athletics fields, a golf driving range, greenways, playgrounds, and picnic grounds.

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Randalls and Wards Islands -

In the mid-19th century, a number of hospitals, asylums, and detention centers were built on both islands, among them the New York House of Refuge (illustrated). Wards Island today is home to the Manhattan Psychiatric Center.

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Governors Island -

Anchored in New York Harbor, Governors Island can only be accessed by ferries from Brooklyn and Manhattan. It's the location of the Governors Island National Monument and a collection of 52 historic buildings. The island is a popular seasonal tourist destination open to the public between May and September.

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Governors Island -

The island originally served as an outpost to protect New York City from sea attack. Its use as a military installation dates back to 1776, during the American Revolutionary War. It was subsequently used as a strategic defensive position in the War of 1812 and the Civil War.

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North Brother Island -

North and South Brother Islands are a pair of small islands located in New York City's East River. North Brother Island was the location of Riverside Hospital (pictured) from 1885 to the late 1930s. It operated as a smallpox hospital.

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North Brother island -

In 1943, a tuberculosis facility opened. This is where the infamous Mary Mallon, known as "Typhoid Mary," was quarantined. Mallon is believed to have infected 51 people, three of whom died, with typhoid fever. She passed away at Riverside in 1938 after spending nearly three decades in isolation.

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Glen Island -

Glen Island in Long Island Sound is known for the Glen Island Park. Established in 1879 by former US Congressman John H. Starin, the recreational facility was originally named Starin's Glen Island.

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Glen Island -

Essentially a summer resort for city dwellers, the park is often referred to as the country's first "theme park" due to the natural history museum, zoo, German beer garden, and castle that greeted visitors when it opened in 1881. Some of these attractions, including the castle, still stand today.

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Roosevelt Island -

Once known as Hog Island (in pre-colonial times), Blackwell's Island, and later still Welfare Island, when it was used principally for hospitals from 1921 to 1973, this slither of a landmass in New York City's East River was ultimately named Roosevelt Island after Franklin D. Roosevelt, the 32nd president of the United States.

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Roosevelt Island -

Roosevelt Island is known for its 18th- and 19th-century architecture. This includes the ruins of a smallpox hospital (pictured), which opened in 1856.

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Mill Rock -

Lying at the confluence of the East River and the Harlem River, Mill Rock (top left) originally served as a fortification during the War of 1812.

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Mill Rock -

The robust fortification was part of a chain of blockhouses that was intended to defend New York Harbor and protect the passage into Long Island Sound against the British Navy. Closed to the public, Mill Rock today serves as a sanctuary for various birdlife.

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Hunter Island -

Situated on the western end of Long Island Sound, Hunter Island is, in fact, now part of a peninsular. The land surrounding the island was originally settled by the Siwanoy Native Americans. By the 18th century, however, the area had been claimed by colonists.

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Hunter Island -

The island is named after New York businessman and politician John Hunter, who purchased the land in 1804. He built a grand mansion (pictured abandoned in 1936) and resided here until 1865. Today the former island is a popular wildlife reserve.

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Rikers Island -

Located in the East River between Queens and the Bronx, Rikers Island is synonymous with one facility—Rikers Island jail, one of the world's largest correctional and mental institutions.

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Rikers Island -

Used as a military training ground during the Civil War, the island is thought to be named after Abraham Rycken, a Dutch settler who moved to Long Island in 1638 and whose descendants owned Rikers Island until 1884. The jail opened in 1932, which is pictured here in 1955.

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Shooters Island -

An uninhabited island at the southern end of Newark Bay, Shooters Island was used by George Washington as a drop-off point for dispatches during the Revolutionary War. As such, it became a hot bed for spies and other treacherous individuals.

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Shooters Island -

During the late 18th century, Shooters Island was home to a major shipyard. Yachts, schooners, and paddle steamers, including the Jane Moseley (pictured) were built here. Allowed to fall into disrepair in the 20th century, the shipyard was eventually abandoned. Today, the island is an official bird sanctuary.

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Davids' Island -

Davids' Island is moored off the coast of New Rochelle, in Long Island Sound. Now uninhabited, the island supports a rich ecosystem of wetlands, rare rocky intertidal areas, and sandy beaches. The destination is home to the critically endangered Kemp's ridley sea turtle, and birds such as osprey and least terns.

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Davids' Island -

From colonial times to the early 20th century, however, Davids' Island was a thriving community. During the Civil War, a large hospital was maintained here to treat both Union and Confederate wounded. The island later became a prominent army recruitment and training center. Fort Slocum, a US military post, occupied the island from 1867 to 1965.

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Swinburne Island -

Swinburne Island is found in the Lower New York Bay, off the South Beach of Staten Island.

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Swinburne Island -

An artificial island, Swinburne originally served as a quarantine station for immigrants, built along with neighboring Hoffman Island by the government after concerns were raised about recent cholera pandemics. Swinburne Island hospital, built in 1879, housed patients until well into the 20th century. Both islands are now managed by the National Park Service.

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Ellis Island -

One of New York's City's most familiar islands, Ellis Island was once the United States' busiest immigrant inspection station, processing around 12 million people between 1892 and 1954.

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Ellis Island -

In the 19th century, Ellis Island was home to a military installation. During both WWI and WWII, its immigration inspection facilities were also used to detain prisoners of war.

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Liberty Island -

One of the most visited islands in the New York City area, Liberty Island is best known as home to the landmark Statue of Liberty. The island is listed on the National Register of Historic Places as part of the Statue of Liberty National Monument, Ellis Island, and Liberty Island.

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Liberty Island -

Liberty Island was called Bedloe's Island until 1956. But the famous monument, a gift from the people of France, had been a feature of the island since the late 19th century, having been dedicated in 1886. It's pictured here in 1893.

See also: The world's largest artificial islands.

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