New York State Route 9A in the context of "Tarrytown, New York"

The Joe DiMaggio Highway, commonly called the West Side Highway and formerly the Miller Highway, is a 5.42-mile-long (8.72 km) mostly surface section of New York State Route 9A (NY 9A), running 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. North of 72nd Street, the roadway continues as the Henry Hudson Parkway.

The current highway was complete by 2001, but required reconstruction after the September 11 attacks that year, when the collapse of the World Trade Center caused debris to fall onto the surrounding areas, damaging the highway. It uses the surface streets that existed before the elevated highway was built: West Street, Eleventh Avenue and Twelfth Avenue. A short section of Twelfth 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.

The Henry Hudson Parkway is a 10.95-mile (17.62 km) controlled-access parkway in New York City. The southern terminus is in Manhattan at 72nd Street, where the parkway continues south as the West Side Highway. It is often erroneously referred to as the West Side Highway throughout its entire course in Manhattan. The northern terminus is at the Bronx–Westchester county line, where it continues north as the Saw Mill River Parkway. All but the northernmost mile of the road is co-signed as New York State Route 9A (NY 9A). In addition, the entirety of the parkway is designated New York State Route 907V (NY 907V), an unsigned reference route.

The owners of the parkway are the New York State Department of Transportation, New York City Department of Transportation, New York City Department of Parks and Recreation, Metropolitan Transportation Authority, Amtrak, and Port Authority of New York and New Jersey. The Henry Hudson Parkway was created by the Henry Hudson Parkway Authority, which was run by "master builder" Robert Moses. The highway itself was constructed from 1934 to 1937.

The West Side Elevated Highway (West Side Highway or Miller Highway, named for Julius Miller, Manhattan borough president from 1922 to 1930) was an elevated section of New York State Route 9A (NY 9A) running along the Hudson River in the New York City borough of Manhattan to the tip of the island. It was an elevated highway, one of the first urban freeways in the world, and served as a prototype for urban freeways elsewhere, including Boston's Central Artery.

Built between 1929 and 1951, the highway had narrow confines—which could not accommodate trucks—and sharp S exit ramps that made it obsolete almost immediately. Maintenance was minimal, and the use of corrosive salts to de-ice the highway in winter accelerated its decay. When chunks of its facade began to fall off due to lack of maintenance, and a truck and car fell through it at 14th Street in 1973, the highway was shut down, and a debate began over whether to renovate it or dismantle it. Attitudes to urban planning had changed in the intervening decades, and the decision was made not to repair the decaying structure.