New York Offshore: Exploring U Thant Island

By Y.M. Lowy

In our summer series New York Offshore, we take a closer look at the islands scattered across New York City’s waterways. Each one carries its own history, landscape, and role in the life of the city, from lively public spaces to quiet, restricted land surrounded by water. This week we explore U Thant Island.

Barely two acres in size, U Thant Island sits in the East River between Manhattan and Queens, just south of the Roosevelt Island Bridge. Thousands of people pass it every day by car, subway, tram, or boat, often without realizing a tiny island is hidden below.

Originally known as Belmont Island, the tiny islet didn’t exist naturally. It was created in the early 1900s from rock excavated during the construction of the Steinway Tunnel beneath the East River, now used by the 7 subway line. The man-made island was named after financier August Belmont Jr., whose company helped build the tunnel.

In 1977, the island was informally renamed after U Thant, the third Secretary-General of the United Nations, who had a deep appreciation for nature and meditation. While the name was never made official by New York State, it has become the one most people use today.

Unlike nearly every other island in this series, U Thant Island has no homes, businesses, or public attractions. It is closed to visitors and serves as a protected sanctuary for nesting birds, including black-crowned night herons, cormorants, and other species that have found a rare refuge in the middle of one of the world’s busiest cities.

Today, the island remains untouched by the crowds surrounding it. Visitors cannot legally step foot on the small island. Because human interference can disrupt the nesting birds, the island is fenced off and closed to visitors. Hidden in plain sight, it remains one of the city’s most unusual and least-known islands.