The Downtown Hudson Tubes are a pair of tunnels that carry PATH trains under the Hudson River in the United States, between New York City to the east and Jersey City, New Jersey, to the west. The tunnels run between the World Trade Center station on the New York side and the Exchange Place station on the New Jersey side.

The Port Authority Trans-Hudson (PATH) is a 13.8-mile (22.2 km) rapid transit system in the northeastern New Jersey cities of Newark, Harrison, Jersey City, and Hoboken, as well as Lower and Midtown Manhattan in New York City. It is operated as a wholly owned subsidiary of the Port Authority of New York and New Jersey. PATH trains run around the clock year-round; four routes serving 13 stations operate during the daytime on weekdays, while two routes operate during weekends, late nights, and holidays. It crosses the Hudson River through cast iron tunnels that rest on the river bottom. It operates as a deep-level subway in Manhattan and the Jersey City/Hoboken riverfront; from Grove Street in Jersey City to Newark, trains run in open cuts, at grade level, and on elevated track. In 2023, the system saw 55,109,100 rides, or about 187,000 per weekday in the fourth quarter of 2023.