In 1924, the IND submitted its list of proposed subway routes to the New York City Board of Transportation (NYCBOT), which approved the program. The IND's program consisted of two lines underneath Sixth Avenue in Manhattan. The first line would be a section in Lower Manhattan between Lispenard Street to the south and Eighth Street to the north, comprising part of the present-day Eighth Avenue Line. The second line would be a section running between Carmine Street to the south and 53rd Street to the north, comprising much of the present-day Sixth Avenue Line. South of Carmine Street, the Sixth Avenue Line would curve east under Houston Street, then south under Essex Street and Rutgers Street before continuing south into Brooklyn.