Manhattan  is the most densely populated borough of New York City, its economic and administrative center, and the city's historical birthplace. The borough is coterminous with New York County, founded on November 1, 1683 as one of the original counties of the U.S. state of New York. The borough consists mostly ofManhattan Island, bounded by the East, Hudson, and Harlem Rivers, and also includes several small adjacent islands and Marble Hill, a small neighborhood on the U.S. mainland.

Manhattan is often described as the cultural and financial capital of the world  and hosts the United Nations Headquarters. Anchored by Wall Street in the Financial District of Lower Manhattan, New York City has been called both the most economically powerful city and the leading financial center of the world, and Manhattan is home to the world's two largest stock exchanges by total market capitalization: the New York Stock Exchange andNASDAQ. Many multinational media conglomerates are based in the borough. It is historically documented to have been purchased by Dutch colonists from Native Americans in 1626, for 60 guilders or about $24 in 1626 and US$1050 today. Manhattan real estate has since become among the most expensive in the world, with the value of Manhattan Island, including real estate, estimated to exceed US$3 trillion in 2013;[2][16] residential property sale prices in Manhattan typically exceeded US$1,400 per square foot ($15,000/m2) as of 2016.[17]

New York County is the United States' second-smallest county by land area (larger only than Kalawao County, Hawaii), and is also the most densely populated U.S. county. It is also one of the most densely populated areas in the world, with a census-estimated 2015 population of 1,644,518 living in a land area of 22.83 square miles (59.13 km2), or 72,033 residents per square mile (27,812/km2), higher than the density of any individual American city. On business days, the influx of commuters increases that number to over 3.9 million,[21] or more than 170,000 people per square mile (65,600/km2). Manhattan has the third-largest population of New York City's five boroughs, after Brooklyn and Queens, and is the smallest borough in terms of land area.

Many districts and landmarks in Manhattan have become well known, as New York City received a record of nearly 60 million tourists in 2015, and Manhattan hosts three of the world's 10 most-visited tourist attractions in 2013: Times Square, Central Park, and Grand Central Terminal. The borough hosts many world-renowned bridges, such as theBrooklyn Bridge; skyscrapers such as the Empire State Building, one of the tallest skyscrapers in the world; and parks, such as Central Park. There are many historically significant places in Manhattan: Chinatown incorporates the highest concentration of Chinese people in the Western Hemisphere, and the Stonewall Inn in Greenwich Village is considered the birthplace of the modern gay rights movement. The City of New York was founded at the southern tip of Manhattan, and the borough houses New York City Hall, the seat of the City's Government. Numerous colleges and universities are located in Manhattan, including Columbia University, New York University, andRockefeller University, which have been ranked among the top 35 in the world