Geography of New York City the coast of the Northeastern United States at the mouth of the Hudson River in southeastern New York state. It is located in the New York–New Jersey Harbor Estuary, the centerpiece of which is the New York Harbor, whose deep waters and sheltered bays helped the city grow in significance as a trading city. Much of New York is built on the three islands of Manhattan, Staten Island, and western Long Island, making land scarce and encouraging a high population density. The Hudson River flows from the Hudson Valley into New York Bay, becoming a tidal estuary that separates the
Geography of New York City Bronx and Manhattan from Northern New Jersey. The Harlem River, another tidal strait between the East and Hudson Rivers, separates Manhattan from the Bronx. The boroughs of New York City straddle the border between two geologic provinces of eastern North America. Brooklyn and Queens, located on Long Island, are part of the eastern coastal plain. Long Island is a massive moraine which formed at the southern fringe of the Laurentide Ice Sheet during the last Ice Age. The Bronx and Manhattan lie on the eastern edge of the Newark Basin, a block of the Earth's crust which sank downward during