U.S. Route 1 (US 1) is a part of the U.S. Highway System that extends from Key West, Florida, to the Canada–United States border at Fort Kent, Maine. In the U.S. state of New York, US 1 extends 21.54 miles (34.67 km) from the George Washington Bridge in Manhattan to the Connecticut state line at Port Chester. It closely parallels Interstate 95 (I-95) for much of its course and does not serve as a major trunk road within the state. It is not concurrent with any other highways besides I-95 and (briefly) US 9, and few other state highways intersect it.

U.S. Route 1/9 is the 31.01-mile (49.91 km) long concurrency of US 1 and US 9 from their junction in Woodbridge Township in Middlesex County, New Jersey, north to New York City. The route is a multilane road with some freeway portions that runs through urbanized areas of North Jersey adjacent to New York City. Throughout most of its length in New Jersey, the road runs near the New Jersey Turnpike/Interstate 95 (I-95). In Fort Lee, US 1/9 merges onto I-95 and crosses the Hudson River on the George Washington Bridge, where the two U.S. Routes split a short distance into New York. US 1/9 intersects several major roads, including I-278 in Linden, Route 81 in Elizabeth, I-78 and US 22 in Newark, Route 139 in Jersey City, Route 3 and Route 495 in North Bergen, and US 46 in Palisades Park. US 1/9 also serves as the primary access point to Newark Airport. Between Newark and Jersey City, US 1/9 runs along the Pulaski Skyway. Trucks are banned from this section of road and must use US 1/9 Truck. The concurrency between US 1 and US 9 is commonly referred to as "1 and 9". Some signage for the concurrency, as well as the truck route, combines the two roads into one shield, separated by a hyphen (1-9) or an ampersand (1&9).