The Clark Street station is a station on the IRT Broadway–Seventh Avenue Line of the New York City Subway. It is located at Clark Street and Henry Street in Brooklyn Heights, Brooklyn. It is served by the 2 train at all times and the 3 train at all times except late nights. At approximately 80 feet (24 m) deep, the Clark Street station contains one island platform and two tracks. Its only exit is via a set of three elevators, which lead from a passageway above the platform to the ground story of the Hotel St. George. Despite being one of three New York City Subway stations that can only be accessed by elevators, the Clark Street station is not wheelchair-accessible with only stairs leading to the platforms.

The IRT Broadway–Seventh Avenue Line is a New York City Subway line. It is one of several lines that serves the A Division, stretching from South Ferry in Lower Manhattan north to Van Cortlandt Park–242nd Street in Riverdale, Bronx. The Brooklyn Branch, known as the Wall and William Streets Branch during construction, 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. The IRT Broadway–Seventh Avenue Line is the only line to have elevated stations in Manhattan, with two short stretches of elevated track at 125th Street and between Dyckman and 225th Streets.