Park Avenue Tunnel (railroad)
Coordinates: 40°47′14″N 73°57′7.3″W / 40.78722°N 73.952028°W
The Park Avenue Tunnel carries four tracks of the Metro-North Railroad underground from Grand Central Terminal at 42nd Street to a portal at 97th Street in the New York City borough of Manhattan. The tracks rise to a full viaduct by 99th Street.
The New York and Harlem Railroad first opened a horsecar line on this route to Harlem station at 125th Street in 1837. The New York Central and Hudson River Railroad lowered the tracks into the 600 feet (180 m) passage which was originally known as the Yorkville Tunnel, built from 1872 to 1876 through Mount Pleasant from 59th to 96th Street, concurrent with the construction of Grand Central Depot. However, as train traffic to Grand Central increased dramatically to the end of the 19th century, the operation of steam locomotives in the tunnel resulted in both an extremely unpleasant experience for riders and a dangerously low level of visibility for train engineers.
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