The West Side Highway (officially the Joe DiMaggio Highway) is a mostly surface section of New York State Route 9A (NY 9A) that runs from West 72nd Street along the Hudson River to the southern tip of Manhattan in New York City. It replaced the West Side Elevated Highway, built between 1929 and 1951, which was shut down in 1973 due to neglect and lack of maintenance, and was dismantled by 1989. The term "West Side Highway" is often mistakenly used, particularly by the news media traffic reporters, to include the roadway north of 72nd Street which is properly known as the Henry Hudson Parkway.

The current highway was complete by 2001, but required some reconstruction due to damage sustained in the 9/11 attacks. It uses the surface streets that existed before the elevated highway was built: West Street, Eleventh Avenue and Twelfth Avenue. A short section of 12th Avenue still runs between 125th and 138th Streets, under the Riverside Drive Viaduct. Eleventh Avenue is a separate street north of 22nd Street. The portion between West 42nd Street and Canal Street is part of the Lincoln Highway.