Cobble Hill Tunnel

The Cobble Hill Tunnel is an abandoned Long Island Rail Road tunnel beneath Atlantic Avenue in Brooklyn, New York City, running through the neighborhoods of Downtown Brooklyn and Cobble Hill. When open, it ran for about 2,517 feet between Columbia Street and Boerum Place. It is the oldest railway tunnel beneath a city street in North America that was fully devoted to rail.
Originally built as an open cutting, construction began in May 1844, and opened for use on December 3, 1844, but was not completely finished until late Spring 1845. It was built mainly to satisfy public demand for creation of a grade-separated right of way for the Brooklyn and Jamaica Railroad on its way to the South Ferry at the foot of Atlantic Street , where passengers could catch ferries to Manhattan. The construction of the cutting also lowered the LIRR's grade through Cobble Hill. Around five years after opening the cutting was roofed over, converting it into a tunnel.

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