Fifth Avenue is a major thoroughfare in the center of the borough of Manhattan in New York City, New York, United States. The section of Fifth Avenue that crosses Midtown Manhattan, especially that between 49th Street and 60th Street, is lined with prestigious shops and is consistently ranked among the most expensive shopping streets in the world. The "most expensive street in the world" moniker changes depending on currency fluctuations and local economic conditions from year to year. For several years starting in the mid-1990s, the shopping district between 49th and 57th Streets was ranked as having the world's most expensive retail spaces on a cost per square foot basis. In 2008, Forbes magazine ranked Fifth Avenue as being the most expensive street in the world. Some of the most coveted real estate on Fifth Avenue are the penthouses perched atop the buildings.

Fifth Avenue originates at Washington Square Park in Greenwich Village and runs northwards through the heart of Midtown, along the eastern side of Central Park, where it forms the boundary of the Upper East Side and through Harlem, where it terminates at the Harlem River at 142nd Street. Traffic crosses the river on the Madison Avenue Bridge. Fifth Avenue serves as the dividing line for house numbering in Manhattan. It separates, for example, East Fifty-ninth Street from West Fifty-ninth Street. From this zero point for street addresses, numbers increase in both directions as one moves away from Fifth Avenue, with 1 West Fifty-ninth Street on the corner at Fifth Avenue, and 300 West Fifty-ninth Street located three blocks to the west of it.