Harlem is a neighborhood in Upper Manhattan, New York City. It is bounded roughly by the Hudson River on the west; the Harlem River and 155th Street on the north; Fifth Avenue on the east; and Central Park North on the south. The greater Harlem area encompasses several other neighborhoods and extends west and north to 155th Street, east to th…Harlem is a neighborhood in Upper Manhattan, New York City. It is bounded roughly by the Hudson River on the west; the Harlem River and 155th Street on the north; Fifth Avenue on the east; and Central Park North on the south. The greater Harlem area encompasses several other neighborhoods and extends west and north to 155th Street, east to the East River, and south to Martin Luther King Jr. Boulevard, Central Park, and East 96th Street.