High Quality Content by WIKIPEDIA articles! The IRT Broadway – Seventh Avenue Line (also known as the Seventh Avenue Line) is a New York City Subway line. It is one of several lines that serves the A Division (IRT), stretching from South Ferry in Lower Manhattan north to Van Cortlandt Park – 242nd Street in Riverdale, Bronx. The Brooklyn Branch, from the main line at Chambers Street southeast through the Clark Street Tunnel to Borough Hall in Downtown Brooklyn, is also part of the Broadway – Seventh Avenue Line.