The City of New York is the most populous city in the United States, while the New York metropolitan area ranks among the world's most populous urban areas. It is a leading global city, exerting a powerful influence over worldwide commerce, finance, culture and entertainment. The city is also an important center for international affairs, hosting the United Nations headquarters.
New York City is located in the Northeastern United States, in southeastern New York State, approximately halfway between Washington, D.C and Boston. The location at the mouth of the Hudson River, which feeds into a naturally sheltered harbor and then into the Atlantic Ocean, has 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 Long Island, making land scarce and encouraging a high population density.