Madison Avenue is a north-south avenue in the borough of Manhattan in New York City which carries northbound one-way traffic. It runs from Madison Square (at 23rd Street) to the Madison Avenue Bridge at 138th Street. In doing so, it passes through Midtown, the Upper East Side (including Carnegie Hill), Spanish Harlem, and Harlem. It is named for and arises from Madison Square, which is itself named for James Madison, the fourth President of the United States.
Madison Avenue was not part of the original New York City street grid established in the Commissioners' Plan of 1811, and was carved between Park and Fifth Avenues in 1836, due to the effort of lawyer and real estate developer Samuel B. Ruggles, a graduate of Yale University who had previously purchased and developed New York's Gramercy Park in 1831, who was in part responsible for the development of Union Square, and who also named Lexington Avenue.
The term "Madison Avenue" serves as a symbol or metaphor for advertising, and Madison Avenue became identified with the advertising industry after the explosive growth in this area in the 1920s.
According to "The Emergence of Advertising in America," an online exhibit at the John W. Hartman Center for Sales, Advertising & Marketing History at Duke University, by the year 1861 there were twenty advertising agencies in New York City, and in 1911, the New York City Association of Advertising Agencies was founded, predating the establishment of the American Association of Advertising Agencies by several years.
A review of some of the architectural findings and history of Madison Avenue can be found in the external links below.
See also: List of toponyms, Fleet Street