National Docks Secondary is a freight rail line within Conrail's North Jersey Shared Assets Area in Hudson County, New Jersey, used by CSX Transportation. It provides access for the national rail network to maritime, industrial, and distribution facilities at Port Jersey, the Military Ocean Terminal at Bayonne (MOTBY), and Constable Hook as well as carfloat operations at Greenville Yard. The line is an important component in the planned expansion of facilities in the Port of New York and New Jersey. The single track right of way comprises rail beds, viaducts, bridges, and tunnels originally developed at the end of the 19th century by competing railroads.

Port Jersey, officially the Port Jersey Port Authority Marine Terminal and referred to as the Port Jersey Marine Terminal, is an intermodal freight transport facility that includes a container terminal located on the Upper New York Bay in the Port of New York and New Jersey. The municipal border of the Hudson County cities of Jersey City and Bayonne runs along the long pier extending into the bay.