The Grand Central–42nd Street station (also signed as 42nd Street–Grand Central) is a major station complex of the New York City Subway. Located in Midtown Manhattan at 42nd Street between Madison and Lexington Avenues, it serves trains on the IRT Lexington Avenue Line, the IRT Flushing Line and the 42nd Street Shuttle. The complex is served by the , , and trains at all times; the and 42nd Street Shuttle (S) trains at all times except late nights; the <6> train during weekdays in the peak direction; and the <7> train during rush hours and early evenings in the peak direction. The station is adjacent to Grand Central Terminal, which serves all Metro-North Railroad lines east of the Hudson River. There are multiple exits to Grand Central Terminal and to nearby buildings such as One Vanderbilt and the Chrysler Building. Numerous elevators make the station compliant with the Americans with Disabilities Act of 1990. The present shuttle station was constructed for the Interborough Rapid Transit Company (IRT) as an express station on the city's first subway line, which was approved in 1900. The station opened on October 27, 1904, as one of the original 28 stations of the New York City Subway. As part of the Dual Contracts, the Flushing Line platform opened in 1915. After the Lexington Avenue Line platforms opened in 1918, the original station became the eastern terminal of the 42nd Street Shuttle, reconfigured with three tracks and two platforms. The Grand Central–42nd Street station complex has been reconstructed numerous times over the years, including in the early 21st century, when the shuttle station was reconfigured. Grand Central–42nd Street is the second busiest station in the -station system, with 45,745,700 passengers in 2019; only the Times Square station complex has more riders. History First subway Planning for a subway line in New York City dates to 1864. However, development of what would become the city's first subway line did not start until 1894, when the New York State Legislature authorized the Rapid Transit Act. The subway plans were drawn up by a team of engineers led by William Barclay Parsons, chief engineer of the Rapid Transit Commission. It called for a subway line from New York City Hall in lower Manhattan to the Upper West Side, where two branches would lead north into the Bronx. A plan was formally adopted in 1897, which called for the subway