Interstate 80 (I-80) is an east–west transcontinental freeway that crosses the United States from San Francisco, California, to Teaneck, New Jersey, in the New York metropolitan area. The highway was designated in 1956 as one of the original routes of the Interstate Highway System; its final segment was opened in 1986. The second-longest Interstate Highway in the United States after I-90, it runs through many major cities, including Oakland, Sacramento, Reno, Salt Lake City, Omaha, Des Moines, and Toledo and passes within 10 miles (16 km) of Chicago, Cleveland, and New York City.
Interstate 29 (I-29) is an Interstate Highway in the Midwestern United States. I-29 runs from Kansas City, Missouri, at a junction with I-35 and I-70, to the Canada–US border near Pembina, North Dakota, where it connects with Manitoba Provincial Trunk Highway 75 (PTH 75), which continues on to Winnipeg. The road follows the course of three major rivers, all of which form the borders of US states. The southern portion of I-29 closely parallels the Missouri River from Kansas City northward to Sioux City, Iowa, where it crosses and then parallels the Big Sioux River. For the northern third of the highway, it closely follows the Red River of the North. The major cities that I-29 connects to includes Council Bluffs, Iowa; Sioux City, Iowa; Sioux Falls, South Dakota; Fargo, North Dakota; and Grand Forks, North Dakota. I-29 also serves as a road connection between the four largest public universities in the Dakotas: the University of North Dakota, North Dakota State University, the University of South Dakota, and South Dakota State University.
U.S. Route 12 or U.S. Highway 12 (US 12) is an east–west United States Numbered Highway, running from Aberdeen, Washington, to Detroit, Michigan, for almost 2,500 miles (4,000 km). The highway has mostly been superseded by Interstate 90 (I-90) and I-94, but, unlike most U.S. Highways that have been superseded by an Interstate, US 12 remains intact as an important link for local and regional destinations. The highway's western terminus in Aberdeen is at an intersection with US 101, while the highway's eastern terminus in Downtown Detroit is at the corner of Michigan and Cass avenues, near Campus Martius Park.
U.S. Route 30 or U.S. Highway 30 (US 30) is an east–west main route of the United States Numbered Highway System, with the highway traveling across the Northern U.S. With a length of 3,112 miles (5,008 km), it is the third-longest U.S. Highway, after US 20 and US 6. The western end of the highway is at US 101 in Astoria, Oregon; the eastern end is at Virginia Avenue, Absecon Boulevard, and Adriatic Avenue in Atlantic City, New Jersey. The "0" as the last digit in the number indicates that it is a coast-to-coast route and a major east–west route. Despite long stretches of parallel and concurrent Interstate Highways, it has not been decommissioned unlike other long-haul routes such as US 66. It is also the only U.S. Highway that has always been coast-to-coast since the beginning of U.S. Numbered Highway System.
U.S. Route 77 is a major north–south United States Numbered Highway which extends for 1,305 miles (2,100 km) in the central United States. As of 2005, Its southern terminus is in Brownsville, Texas, at Veteran's International Bridge on the Mexican border, where it connects with both Mexican Federal Highway 101 and Mexican Federal Highway 180, and the highway's northern terminus is in Sioux City, Iowa, at an interchange with Interstate 29 (I-29), less than 1⁄2 mile (800 m) north of the Nebraska state line.
U.S. Route 20 or U.S. Highway 20 (US 20) is an east–west United States Numbered Highway that stretches from the Pacific Northwest east to New England. The "0" in its route number indicates that US 20 is a major coast-to-coast route. Spanning 3,365 miles (5,415 km), it is the longest road in the United States, and, in the east, the route is roughly parallel to Interstate 90 (I-90), which is the longest Interstate Highway in the U.S. There is a discontinuity in the official designation of US 20 through Yellowstone National Park, with unnumbered roads used to traverse the park.
U.S. Route 40 or U.S. Highway 40 (US 40), also known as the Main Street of America, is a major east–west United States Highway traveling across the United States from the Mountain States to the Mid-Atlantic States. As with most routes whose numbers end in a zero, US 40 once traversed the entire United States. It is one of the first U.S. Highways created in 1926 and its original termini were in San Francisco, California, and Atlantic City, New Jersey. US 40 currently ends at a junction with I-80 in Silver Summit, Utah, just outside Salt Lake City. West of this point US 40 was functionally replaced with I-80, and as these segments of I-80 were constructed the western portion of US 40 was truncated several times.
U.S. Route 52 (US 52) is a major United States highway in the central United States that extends from the northern to southeastern region of the United States. Contrary to most other even-numbered U.S. Highways, US 52 primarily follows a northwest–southeast route, and is signed north–south or east–west depending on the local orientation of the route. The highway's northwestern terminus is in Portal, North Dakota at the Canada–United States border, where it continues as Saskatchewan Highway 39. Its southeastern terminus is in Charleston, South Carolina, at Number 2 Meeting Street and White Point Garden along the Charleston Harbor.
U.S. Route 59 is a north–south United States highway. A latecomer to the U.S. numbered route system, US 59 is now a border-to-border route, part of the NAFTA Corridor Highway System. It parallels U.S. Route 75 for nearly its entire route, never much more than 100 miles (160 km) away, until it veers southwest in Houston, Texas. Its number is out of place since US 59 is either concurrent with or entirely west of U.S. Route 71. The highway's northern terminus is 9 mi (14 km) north of Lancaster, Minnesota, at the Lancaster–Tolstoi Border Crossing on the Canada–US border, where it continues as Manitoba Highway 59. Its southern terminus is at the Mexico–US border in Laredo, Texas, where it continues as Mexican Federal Highway 85D.
U.S. Route 71 or U.S. Highway 71 is a major north–south United States highway that extends for over 1500 miles (2500 km) in the central United States. This original 1926 route has remained largely unchanged by encroaching Interstate highways. Currently, the highway's northern terminus is in International Falls, Minnesota at the Canada–US border, at the southern end of the Fort Frances-International Falls International Bridge to Fort Frances, Ontario. U.S. Route 53 also ends here. On the other side of the bridge, Trans-Canada Highway is an east–west route while Ontario Highway 71 is a north–south route. US 71's southern terminus is between Port Barre and Krotz Springs, Louisiana at an intersection with U.S. Route 190. For the entirety south of Kansas City, Missouri, US 71 runs parallel and concurrent with the existing and future Interstate 49. North of Kansas City, US 71 runs halfway between Interstate 29 and Interstate 35, which they split in the city at an interchange with Interstate 70.
U.S. Route 202 (US 202) is a spur route of US 2. It follows a northeasterly and southwesterly direction stretching from Delaware in the south to Maine in the north and traveling through the states of Pennsylvania, New Jersey, New York, Connecticut, Massachusetts, and New Hampshire. The highway has borne the number 202 since at least 1936. Before this, sections of the highway were designated U.S. Route 122, as it intersected US 22 in New Jersey. It intersects its parent route, US 2, in Bangor, Maine.
U.S. Route 19 or U.S. Highway 19 (US 19) is a north–south United States Numbered Highway in the Eastern United States. Despite encroaching Interstate Highways, the route has remained a long-haul road, connecting the Gulf of Mexico with Lake Erie.
U.S. Route 62 or U.S. Highway 62 (US 62) is an east–west United States Highway in the southern and northeastern United States. It runs from the Mexican border at El Paso, Texas, to Niagara Falls, New York, near the Canadian border. It is the only east–west United States Numbered Highway that connects Mexico and Canada. Parts of US 62 follow what once was the Ozark Trail, including the historic bridge across the South Canadian River in Newcastle, Oklahoma. This bridge was damaged beyond repair by the 2013 Moore tornado that struck Newcastle and Moore, Oklahoma. The highway runs north–south in New York and Pennsylvania.
U.S. Highway 18 (US 18) is an east–west United States Numbered Highway in the Midwestern United States. The western terminus is in Orin, Wyoming, at an interchange with Interstate 25 (I-25). Its eastern terminus is in Downtown Milwaukee, Wisconsin. US 18, however, runs concurrent with other U.S. Highways from its western terminus to Mule Creek Junction, Wyoming. US 18 is one of the original U.S. Highways of 1926. The US 18 designation was originally proposed for a road in Michigan from Grand Haven east to Detroit. This roadway was eventually designated as US 16.
U.S. Route 15 or U.S. Highway 15 (US 15) is a 791.71-mile-long (1,274.13 km) United States Numbered Highway, serving the states of South Carolina, North Carolina, Virginia, Maryland, Pennsylvania, and New York. The route is signed north–south, from US 17 Alternate in Walterboro, South Carolina, north to Interstate 86 (I-86)/New York State Route 17 (NY 17) in Corning, New York.
U.S. Route 63 (US 63) is a 1,286-mile (2,070 km), north–south United States Highway primarily in the Midwestern and Southern United States. The southern terminus of the route is at Interstate 20 (I-20) in Ruston, Louisiana; the northern terminus is at US 2 eight miles (13 km) west of Ashland, Wisconsin.
U.S. Route 6 (US 6) in New York is a 77.85-mile (125.29 km) stretch of United States Numbered Highway that spans from the Pennsylvania state line at Port Jervis to the Connecticut state line east of Brewster. Near both ends it runs in close proximity to Interstate 84 (I-84), which otherwise takes a more northerly route through Downstate New York. US 6, meanwhile, skirts the northern fringe of the New York metropolitan area.
Several special routes of U.S. Route 6 (US 6) exist. In order from west to east, these special routes are as follows.
U.S. Route 209 (US 209) is a 211.74-mile (340.76 km) long U.S. Highway in the states of Pennsylvania and New York. Although the route is a spur of US 9, US 209 never intersects US 9, coming within five miles of the route and making the short connection via New York State Route 199 (NY 199). The southern terminus of the route is at Pennsylvania Route 147 (PA 147) in Millersburg, Pennsylvania. The northern terminus is at US 9W north of Kingston in Ulster, New York, where the road continues east as NY 199.
U.S. Route 44 (US 44) is an east–west United States Numbered Highway that runs for 237 miles (381 km) through four states in the Northeastern United States. The western terminus is at US 209 and New York State Route 55 (NY 55) in Kerhonkson, New York, a hamlet in the Hudson Valley region. The eastern terminus is at Route 3A in Plymouth, Massachusetts.
US 395 in Bishop, CA 
Route 6A in Provincetown, MA 
