58 Joralemon Street, in Brooklyn Heights, Brooklyn, New York, United States, is a Greek Revival structure built in 1847 as a private residence but is now a New York City Subway vent. The Interborough Rapid Transit Company acquired the property in 1907, gutted the interior, and converted the structure to "the world’s only Greek Revival subway ventilator". The ventilator also serves as an emergency exit from the eastern end of the New York City Subway's Joralemon Street Tunnel, which carries the IRT Lexington Avenue Line (4 and ​5 trains) between Bowling Green and Borough Hall, where it becomes the IRT Eastern Parkway Line (2, ​3, ​4, and ​5 trains).