The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, or the Eisenhower Interstate System, is a network of controlled-access highways that forms part of the National Highway System in the United States. The system extends throughout the contiguous United States and has routes in Hawaii, Alaska, and Puerto Rico.
Interstate 68 (I-68) is a 113.15-mile (182.10 km) Interstate Highway in the U.S. states of West Virginia and Maryland, connecting I-79 in Morgantown, West Virginia, east to I-70 in Hancock, Maryland. I-68 is also Corridor E of the Appalachian Development Highway System (ADHS). From 1965 until the freeway's construction was completed in 1991, it was designated as U.S. Route 48 (US 48). In Maryland, the highway is known as the National Freeway, an homage to the historic National Road, which I-68 parallels between Keysers Ridge and Hancock. The freeway mainly spans rural areas and crosses numerous mountain ridges along its route. A road cut at Sideling Hill exposed geological features of the mountain and has become a tourist attraction.
Interstate 73 (I-73) is a north–south Interstate Highway, currently located entirely within the US state of North Carolina. It travels 93.5 miles (150.5 km), from south of Ellerbe, North Carolina to northeast of Stokesdale, providing a freeway connection to Greensboro and Asheboro. Other than a short 9.5 mi (15.3 km) segment near the Piedmont Triad International Airport west of Greensboro, the interstate runs concurrently with at least one other route.
U.S. Route 35 (US 35) is a United States Highway that runs southeast-northwest for approximately 412 miles (663 km) from the western suburbs of Charleston, West Virginia to northern Indiana. Although the highway is physically southeast-northwest, it is nominally north–south. The highway's southern terminus is in Teays Valley, West Virginia, near Scott Depot, at Interstate 64 (I-64). Its northern terminus is near Michigan City, Indiana, at US 20. The West Virginia portion of the highway is mostly expressway, becoming a freeway shortly before it crosses the Ohio River into Ohio. The Ohio portion has been upgraded to a four-lane highway/freeway between the West Virginia state line and Trotwood, west of Dayton.
A concurrency in a road network is an instance of one physical roadway bearing two or more different route numbers. When two roadways share the same right-of-way, it is sometimes called a common section or commons. Other terminology for a concurrency includes overlap, coincidence, duplex, triplex, multiplex, dual routing or triple routing.
U.S. Route 48 (US 48), also known as the incomplete Corridor H of the Appalachian Development Highway System, extends from Interstate 79 (I-79) in Weston, West Virginia, eastward across the crest of the Allegheny Mountains to I-81 in Strasburg, Virginia. It is planned to extend 157 miles (253 km) from northwestern Virginia to central West Virginia.
U.S. Route 730 (US 730) is an east–west United States Numbered Highway, of which all but 6.08 miles of its 41.78 miles are within the state of Oregon. The highway starts in rural Morrow County in Eastern Oregon at an interchange with Interstate 84 (I-84) and US 30, located east of the city of Boardman. US 730 travels east along the Columbia River as a continuation of Columbia River Highway No. 2 into Umatilla County, intersecting I-82 and US 395 in the city of Umatilla. US 730 and US 395 form a short concurrency within the city before the highways part, and US 730 continues northeast into Washington. The highway travels through rural Walla Walla County and ends at an intersection with US 12 south of Wallula.
State Route 7 (SR 7), formerly known as Inter-county Highway 7 until 1921 and State Highway 7 in 1922, is a north–south state highway in the southern and eastern portions of the U.S. state of Ohio. At about 336 miles (541 km) in length, it is the longest state route in Ohio. Its southern terminus is an interchange with U.S. Route 52 (US 52) just west of Chesapeake. Its northern terminus also serves as the eastern terminus of SR 531 in Conneaut. The path of SR 7 stays within five miles (8.0 km) of the Ohio River for the southern portion, with the river being visible from much of the route. The road also remains within 10 miles (16 km) of the Pennsylvania state line for the northern portion.
The West Virginia State Highway System is an integrated system of numbered roads in the U.S. state of West Virginia. These highways were coordinated by the West Virginia Department of Transportation, Division of Highways.
The state highway system of the U.S. state of Virginia is a network of roads maintained by the Virginia Department of Transportation (VDOT). As of 2006, the VDOT maintains 57,867 miles (93,128 km) of state highways, making it the third-largest system in the United States.
Interstate 470 (I-470) is a 10.63-mile-long (17.11 km) auxiliary Interstate Highway of I-70 that bypasses the city of Wheeling, West Virginia, United States. I-470 is one of 13 auxiliary Interstate Highways in Ohio and the only auxiliary Interstate Highway in West Virginia. The western terminus of I-470 is an interchange with I-70 in Richland Township, Ohio. Traveling southeast through rural Belmont County, I-470 approaches the Vietnam Veterans Memorial Bridge, which spans the Ohio River. After crossing the river into Ohio County, West Virginia, the highway continues east toward the Wheeling communities of Bethlehem and Elm Grove and its eastern terminus at I-70 near Elm Grove. The portion of the highway in West Virginia is named the USS West Virginia Memorial Highway by proclamation of then-Governor Cecil H. Underwood on the 59th anniversary of the attack on Pearl Harbor.
The Mon–Fayette Expressway is a partially-completed controlled-access toll road that is planned to eventually link Interstate 68 near Morgantown, West Virginia with Interstate 376 near Monroeville, Pennsylvania. The ultimate goal of the highway is to provide a high speed north–south connection between Morgantown and the eastern side of Pittsburgh while revitalizing economically distressed Monongahela River Valley towns in Fayette and Washington counties, serving as an alternative to Interstate 79 to the west, as well as relieving the PA 51 alignment from Pittsburgh to Uniontown.
A total of at least 31 special routes of U.S. Route 17 (US 17) exist: 3 in Florida, 5 in South Carolina, 17 in North Carolina, and 6 in Virginia.
U.S. Route 25 (US 25) is a 140.600-mile (226.274 km) United States Numbered Highway that travels from Brunswick, Georgia, to the Kentucky–Ohio state line, where Covington, Kentucky, meets Cincinnati, Ohio, at the Ohio River. In the U.S. state of South Carolina, it travels south to north in the western part of the state, serving the northern part of the Augusta metropolitan area, Greenwood, and Upstate South Carolina on its path from North Augusta to North Carolina in the Saluda Mountains, near Travelers Rest.
The primary highway system makes up over 9,000 miles (14,000 km), approximately 8 percent of the U.S. state of Iowa's public road system. The Iowa Department of Transportation is responsible for the day-to-day maintenance of the primary highway system, which consists of Interstate Highways, United States Highways, and Iowa state highways. Currently, the longest primary highway is U.S. Highway 30 at 332 miles (534 km). The shortest highway is Interstate 129 at 0.27 miles (430 m).
Several special routes of U.S. Route 19 (US 19) exist. In order from south to north, they are as follows.
Interstate 87 (I-87) is a partially completed Interstate Highway in the US state of North Carolina, the shortest designated primary Interstate Highway at 12.90 miles (20.76 km). The completed portion is in eastern Wake County, between Raleigh and Wendell; the majority of the completed route is known as the Knightdale Bypass, while the remaining three miles (4.8 km) follows the Raleigh Beltline (I-440). It is planned to continue northeast through Rocky Mount, Williamston, and Elizabeth City, ending in Norfolk, Virginia. It is signed as north–south, in keeping with the sign convention for most odd-numbered interstates, but the route goes primarily east–west, with the eastern direction aligning to the north designation. The entire route is concurrent with US Highway 64 (US 64), with portions also concurrent with I-440 and US 264.
The Delaware State Route System consists of roads in the U.S. state of Delaware that are maintained by the Delaware Department of Transportation (DelDOT). The system includes the portions of the Interstate Highway System and United States Numbered Highways system located in the state along with state routes and other roads maintained by DelDOT. All roads maintained by the state are assigned a maintenance road number that is only marked on little white markers at intersections and on auxiliary plates below warning signs approaching intersections. These numbers are only unique in a specific county; some roads can be designated with multiple road numbers, and numbers do not necessarily correspond to the signed Interstate, U.S., or state route numbers. DelDOT maintains a total of 5,386.14 miles (8,668.15 km) of roads, comprising 89 percent of the roads within the state. Some large bridges in the state are maintained by other agencies including the U.S. Army Corps of Engineers and the Delaware River and Bay Authority. Roads in the system include multilane freeways, multilane surface divided highways, and two-lane undivided roads serving urban, suburban, and rural areas. Some of the roads maintained by DelDOT are toll roads, in which motorists must pay to use.
