New York Harbor is at the mouth of the Hudson River where it empties into New York Bay near the East River tidal estuary, and then into the Atlantic Ocean on the east coast of the United States. It is one of the largest natural harbors in the world. Although the United States Board on Geographic Names does not use the term, New York Harbor has important historical, governmental, commercial, and ecological usages. It is the largest part of the Port of New York and New Jersey.