The Henry Hudson Parkway is a 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 boundary, 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. Route description The Henry Hudson Parkway begins at 72nd Street, which also serves as the north end of the West Side Highway and the last remaining section of the West Side Highway's predecessor, the Miller Highway. The junction is numbered as exit 8, continuing the numbering scheme used on the West Side Highway. It heads northward along the west side of Manhattan, connecting to West 79th Street with a large interchange and to other surface streets with more intermittent exits along the way. The parkway continues in a northerly direction, running almost parallel to Riverside Drive north of West 158th Street. It passes under the Trans-Manhattan Expressway (I-95 and U.S. 1) and the George Washington Bridge as it continues its progression through Fort Washington Park, Fort Tryon Park, and Inwood Hill Park. It then runs northward across the Henry Hudson Bridge into the Bronx. Upon entering the Bronx, the parkway passes through Spuyten Duyvil and Riverdale as it continues northward, edging slightly to the northeast. Between exits 20 and 22, Riverdale Avenue is split into service roads along the parkway. At exit 23, NY 9A leaves the parkway for U.S. Route 9 (US 9) while the parkway enters Van Cortlandt Park. Soon after it enters the park, the parkway has an interchange with the Mosholu Parkway, which connects it to I-87. Less than a mile farther on,