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Barely poking out of the East River off the coast of Manhattan is tiny U Thant Island, a hardly noticeable mound of greenery. What looks like metal scaffolding rising from its base is actually a set of Buddhist monuments.

That the little islet is there at all is due to one of New York's many subway tunnels. Officially named "Belmont Island," U Thant didn't exist until the late 19^th century, when a trolley tunnel was dug beneath the East River to connect Manhattan with Queens. As dirt and rock from the tunnel's construction built up on a pre-existing reef beneath the surface, the island slowly began to emerge above the water level. By the end of the tunnel's construction, a new landmass was born.

Initially the freshly born land was named after the financier who finished the tunnel, August Belmont Jr. In 1977 a Buddhist group known as Peace Meditation at the United Nations rented control of the island from the city and unofficially renamed it after former United Nations Secretary General U Thant, building a skeletal metal arch adorned with mementos of the leader. A sign was also placed on the island heralding its new name, ensuring that it would stick in the decades to come.

Today the island is off-limits, but eagle-eyed sightseers can view it from shore, or pass beneath it on the 7 train that now operates in the old tunnel.

For more on U Thant Island, visit Atlas Obscura.

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