Grand Central Station covers an area of 48 acres and has 44 platforms on two levels, with 67 tracks along them. There are 41 tracks on the upper level and 26 tracks on the lower level. All of them are built underground at the end of a long tunnel under Park Avenue, where trains have to change from diesel to electric power using a third rail to avoid problems with exhaust. These platforms serve commuters traveling on the Metro-North Railroad to Westchester County, New York, Putnam County, New York, and Dutchess County, New York in New York State, and Fairfield County, Connecticut and New Haven County, Connecticut in the state of Connecticut. By December 2022, the Long Island Rail Road will be extended to a new station at Grand Central, below the existing platforms. Once this happens, Grand Central will have a total of 75 tracks and 48 platforms.