Grand Central Terminal (GCT)—colloquially called Grand Central Station, or shortened to simply Grand Central—is a commuter rail terminal station at 42nd Street and Park Avenue in Midtown Manhattan in New York City, United States. Built by and named for the New York Central Railroad in the heyday of American long-distance passenger trains, it is the largest train station in the world by number of platforms: 44, with 67 tracks along them. They are on two levels, both below ground, with 41 tracks on the upper level and 26 on the lower, though the total number of tracks along platforms and in rail yards exceeds 100. When the Long Island Rail Road's new station opens in 2016 (see East Side Access), Grand Central will offer a total of 75 tracks and 48 platforms. The terminal covers an area of 48 acres (19 ha).

The terminal serves commuters traveling on the Metro-North Railroad to Westchester, Putnam, and Dutchess counties in New York State, and Fairfield and New Haven counties in Connecticut. The terminal used to be served by Amtrak, but in 1991 their trains moved to nearby Pennsylvania Station as a result of the completion of the Empire Connection.