A Tiny Island with a Big History
U Thant Island, officially called Belmont Island, is the smallest island in Manhattan. Located in the East River, it was unintentionally created during the construction of the Steinway Tunnel in the early 1900s. The tunnel, which now serves the 7 train, required an excavation shaft, and the debris formed this artificial islet near Roosevelt Island.
A Changing Name and Purpose
Originally named after financier August Belmont Jr., the island remained largely unused. In 1977, followers of Sri Chinmoy, a spiritual leader, unofficially renamed it U Thant Island in honor of the former UN Secretary-General. They planted greenery and attempted to maintain the site, but public access remained restricted as the land belonged to the New York State government.
A Sanctuary in the City
The island is now a sanctuary for nesting birds, particularly double-crested cormorants. A navigational beacon also sits atop the islet to mark the Roosevelt Island Reef. Since 2016, U Thant Island has been designated a Recognized Ecological Complex under New York City’s Waterfront Revitalization Program.
Unusual Events and Symbolic Gestures
In 1972, activists temporarily occupied the island in protest of Soviet policies. In 2004, artist Duke Riley rowed to the island and declared it an independent nation before being stopped by the U.S. Coast Guard. Though uninhabited, U Thant Island continues to capture curiosity, serving as both a historical remnant and an unexpected piece of New York City’s landscape.
A small island in the East River often goes unnoticed. U Thant Island, officially Belmont Island, is Manhattan’s smallest island. It was unintentionally created in the early 1900s when debris from the Steinway Tunnel excavation formed a landmass near Roosevelt Island.🧵👇 pic.twitter.com/jJ8KLG48K7
— Detective Tiger's Stories (@TigerDetective) February 1, 2025