It ends at New York City near the Atlantic Ocean. This river is called the Hudson. The Hudson River changes during this journey. It begins as fresh water flowing from the mountains.

Manhattan is an island surrounded by three distinct bodies of water, though only one is a "true" river in the traditional sense. To the west, separating Manhattan from New Jersey, is the Hudson River (historically called the North River in its lower section). This is a 315-mile river that originates in the Adirondacks. To the east, separating Manhattan from Brooklyn and Queens, is the East River, which is technically not a river at all but a tidal strait connecting the Upper New York Bay to the Long Island Sound. To the north, separating Manhattan from the Bronx, is the Harlem River, which is also a tidal strait connecting the Hudson and East Rivers. These waterways are tidal estuaries, meaning their flow and salinity change with the Atlantic tides. In 2026, the Hudson remains the most iconic of the three, serving as a major shipping lane and providing the dramatic backdrop for the Midtown and World Trade Center skylines. The "Hudson River Park" along the western shore has become one of the city's premier recreational spaces for walking, cycling, and kayaking.