Manhattan, Staten, Riker’s, Governor’s. New York is a city of islands, with only The Bronx connected to the U.S. mainland. The rest of us are in good company, however, as there are dozens of little-known or visited islands around NYC, each (well, most of them) with rich stories of their own. Here are just a few:

City Island

City Island is somewhat of an anachronism in NYC and residents are happy to keep it that way. Located northeast of the Bronx and accessible by a small private bridge, this island is home to a New England-like oceanfront community of around 4,000 (fewer than some blocks in the rest of the city). City Islanders, or “clamdiggers,” consider the place an oasis apart from the rest of the city and can be somewhat insular. If you hope to visit the City Island Nautical Museum or try some of their famous seafood, your best bet to past the security gates is the Bx29 bus.

Hart Island

A stone’s throw from City Island, Hart Island has attained some notoriety in recent years for its burial grounds of unclaimed people and prisoners. Formerly home to a boy’s prison and Civil War POW camps, more than 1 million people have been laid to rest here since it was converted to a municipal cemetery in 1869. Not a hotspot for vacationers, Hart Island visitation is strictly limited to twice per month ferry trips for relatives of the dead and morbidly curious tourists who have requested spots ahead of time.

Hoffman and Swinburne Islands

It might seem farfetched now, but as nearby Fort Wadsworth serves to remind us, New York has historically been a vitally important port during wartime. Hoffman and Swinburne Island, originally created as quarantine stations for immigrants arriving at nearby Ellis Island, also served as training grounds for Merchant Marines during WWII, and more integrally, were designated anchor points for anti-submarine nets to keep the city’s harbors safe. Thankfully, they were never called into duty for this use, and are currently protected lands as part of the Gateway National Recreation Area managed by the U.S. Park Service.

U Thant/Belmont Island

For a spot of land measuring just 100 by 200 feet, this tiny island on the East River has had a colorful history. Made up of materials from the digging of the 7 train tunnels connecting Manhattan and Queens, Belmont Island (named for the tunnels’ financier) became U Thant Island when the land was leased by devout followers of the Indian meditation guru Sri Chinmoy and designated a Buddhist shrine. The island sat quietly until 2004, when in protest of the then-ongoing Republican National Convention, artist and island-hopper Duke Reilly rowed out to the island and declared it a sovereign nation, hanging a homemade flag from the island’s navigation tower. He was taken home by the Coast Guard, and U Thant Island continues to sit peacefully.

North Brother Island

North Brother Island sits southeast of the Bronx and has been the site of some of the more harrowing stories of New York City history. It sat uninhabited until 1885 when the city designated it the site of Riverside Hospital, a place where highly contagious patients could be treated safely away from the rest of the city. It was the home to perhaps the most famous such patient, Typhoid Mary, who notoriously spread the disease around the city as a cook for several wealthy families. Less famously (but more destructively), the island was also the beaching point of the doomed passenger ship the General Slocum, which ran aground on North Brother Island after catching fire in the East River. A memorial to those who lost their lives currently stands in Tompkins Square Park in Manhattan.

Shooter’s Island

An uninformed observer would never guess that this unassuming bird habitat, nestled between Staten Island and New Jersey, was once the dominion of spies fighting the American Revolution. Originally a hunting preserve (hence the name), quiet and isolated Shooter’s Island was designated by George Washington as a drop-off point for top-secret missives used to help topple the British. In post-war years, the island belonged to industry as the home of refineries and shipyards, and was the site of the 1902 launch of Kaiser Wilhelm II of Germany’s private yacht, attended by President Theodore Roosevelt and filmed for posterity by Thomas Edison. Returning to its calm and isolated roots, Shooter’s Island is currently a bird sanctuary.