Interstate 40
Interstate 40 is a major east–west transcontinental Interstate Highway in the southeastern and southwestern portions of the United States. At a length of, it is the third-longest Interstate Highway in the country, after I-90 and I-80. From west to east, it passes through California, Arizona, New Mexico, Texas, Oklahoma, Arkansas, Tennessee, and North Carolina. Its western terminus is at I-15 in Barstow, California, while its eastern terminus is at a concurrency with U.S. Route 117 and North Carolina Highway 132 in Wilmington, North Carolina. Major cities served by the Interstate include Flagstaff, Arizona; Albuquerque, New Mexico; Amarillo, Texas; Oklahoma City, Oklahoma; Fort Smith and Little Rock in Arkansas; Memphis, Nashville, and Knoxville in Tennessee; and Asheville, Winston-Salem, Greensboro, Durham, Raleigh, and Wilmington in North Carolina.
I-40 begins in the Mojave Desert in California, and then proceeds through the Colorado Plateau in Arizona and the southern tip of the Rocky Mountains in New Mexico. It then traverses the Great Plains through the Texas Panhandle and Oklahoma, and passes south of the Ozarks in Arkansas. The freeway crosses the Appalachian Mountains in Tennessee and North Carolina, before terminating in the Atlantic Coastal Plain near the Atlantic Ocean.
Much of the western part of I-40, from Barstow to Oklahoma City, parallels or overlays the historic U.S. Route 66. East of Oklahoma City, the route generally parallels US 64 and US 70. I-40 was established by the Federal-Aid Highway Act of 1956, and the numbering was subsequently approved on August 14, 1957, along with most of the rest of the system. The eastern terminus was initially planned to be located at I-85 in Greensboro, but the Federal Highway Administration later approved extending the route to its current eastern terminus in Wilmington. As a result, this was the last segment of I-40 to be completed upon its dedication in 1990.
Route description
California
I-40 in California crosses through the lightly populated northern part of the Inland Empire region of the state. Its western end is in Barstow, California. Known as the Needles Freeway, it heads east from Barstow across the Mojave Desert in San Bernardino County to Needles, before it crosses the Colorado River into Arizona southwest of Kingman. I-40 covers in California. Some signs show the control city for I-40 westbound to be Los Angeles, where drivers would follow I-15 south from its western terminus in Barstow. The highway is four lanes for the entirety of its length in the state.A sign in California showing the distance to Wilmington, North Carolina, has been stolen several times.
Arizona
I-40 is a main route to the South Rim of the Grand Canyon, with the exits leading into Grand Canyon National Park in Williams and Flagstaff. I-40 covers in Arizona. Just west of exit 190, west of Flagstaff, is its highest elevation along I-40 in the US, as the road crosses just over at the Arizona Divide near milepost 190. I-40 also passes through the Navajo Nation, the largest Indian reservation in the US. Like California's segment, the highway is four lanes for the entirety of its length in the state.New Mexico
I-40 covers in New Mexico. As in other states it parallels or overrides the post 1937 Route 66 route through the state. Notable cities along I-40 include Gallup, Grants, Albuquerque, Santa Rosa, and Tucumcari. I-40 also travels through several Indian reservations in the western half of the state. It reaches its highest point in the state of at the Continental Divide in western New Mexico between Gallup and Grants. The last place that I-40 tops is at the head of Tijeras Canyon east of Albuquerque at approximately.Arizona, New Mexico, Texas, Oklahoma, and Arkansas are the five states where I-40 has a speed limit of instead of the limit in California, Tennessee, and North Carolina.
Texas
In the west Texas panhandle area, there are several ranch roads connected directly to the Interstate. The only major city in Texas that is directly served by I-40 is Amarillo, which connects with I-27 that runs south toward Lubbock. I-40 also connects to US 287 that runs southeast to Dallas–Fort Worth and US 87/US 287 north to Dumas and then on into Oklahoma. I-40 has only one welcome center in the state, which is located in Amarillo at the exit for Rick Husband Amarillo International Airport, serving both sides of the Interstate.Oklahoma
I-40 goes through the heart of the state, passing through many Oklahoma cities and towns, including Erick, Sayre, Elk City, Clinton, Weatherford, El Reno, Yukon, Oklahoma City, Del City, Midwest City, Shawnee, Okemah, Henryetta, Checotah, Sallisaw, and Roland. I-40 covers in Oklahoma.In Downtown Oklahoma City, I-40 was rerouted south of its former alignment and a 10-lane facility replaced the former I-40 Crosstown Bridge; the former I-40 alignment will be replaced with an urban boulevard currently designated as Oklahoma City Boulevard.
Arkansas
I-40 enters the west-central part of the state and runs for in Arkansas. The route passes through Van Buren, where it intersects the southbound I-540/US 71 to Fort Smith. The route continues east to Alma to intersect I-49 north to Fayetteville, Arkansas. Running through the Ozark Mountains, I-40 serves Ozark, Clarksville, Russellville, Morrilton, and Conway. The route turns south after Conway and enters North Little Rock, which brings high volume interchanges with I-430, I-30/US 65/US 67/US 167, and I-440. The Interstate continues east through Lonoke, Brinkley, and West Memphis on the eastside. I-40 briefly overlaps I-55 in West Memphis before it crosses the Mississippi River on the Hernando de Soto Bridge and enters Memphis, Tennessee.Tennessee
The State of Tennessee has the longest segment of I-40 at. The Interstate goes through all of the three Grand Divisions of Tennessee and its three largest cities: Memphis, Nashville, and Knoxville. Jackson, Lebanon, Cookeville, Crossville, and Newport are other notable cities through which I-40 passes. Before leaving the state, I-40 enters the Great Smoky Mountains toward North Carolina.The section of I-40 which runs between Memphis and Nashville is often referred to as the Music Highway. During reconstruction, a short section of I-40 through downtown Knoxville near the central Malfunction Junction was completely closed to traffic from May 1, 2008, and not reopened until June 12, 2009, with all traffic redirected via I-640, the northern bypass route. The redesigned section now has additional lanes in each direction, is less congested, and has fewer accidents.
North Carolina
In North Carolina, I-40 travels. It enters the state as a winding mountain freeway through the Great Smoky Mountains, which frequently closes due to landslides and weather-related problems. It enters the state on a mostly north–south alignment, turning to a more east–west alignment upon merging with US 74 at the eastern terminus of the Great Smoky Mountains Expressway. From there, the highway passes through Asheville, Hickory, and Statesville before reaching the Piedmont Triad. Just east of the Triad City of Greensboro, North Carolina, it merges with I-85, and the two roads split again just west of the Research Triangle area, passing through Durham and Raleigh. From the Triangle to its eastern terminus in Wilmington, it once again takes a more north–south alignment.A standard distance sign existed near the start of the westbound section of I-40 in Wilmington that indicated the distance to Barstow, California, as. In 2009, NCDOT said it would not be replaced after frequent thefts.
History
Predecessors and planning
During the colonial and westward expansion eras, a number of Native American trails existed within the vicinity of what is now Interstate 40. In 1857, an expedition led by Lt. Edward Fitzgerald Beale was tasked with establishing a trade route along the 35th parallel north from Fort Smith, Arkansas, to Los Angeles, California. This route, which became known as Beale's Wagon Road, was constructed by a team of about 100 men and 22 camels led by Beale. Completed in 1859, it is generally considered the first federal highway in the Southwestern United States.In the early 20th century, a number of auto trails were established by private organizations to aid motorists in traveling between major cities. Among these was the National Old Trails Road, which roughly followed the western part of present-day I-40 to Albuquerque, and the Lee Highway, which followed much of the eastern portion of the route. When the state governments established the United States Numbered Highway System in 1926, two of these most important highways, US 66 and US 70 were established within the present-day I-40 corridor.
US 66, which followed the route from its western terminus to Oklahoma City, became arguably the most famous highway in the United States and has been recognized multiple times in popular culture. US 70, which roughly follows the remainder of the Interstate, was also one of the most important highways for east−west travelers, and was considered part of the "Broadway of America" highway between California and New York.
An east−west trans-continental freeway to serve the south-central United States was proposed in multiple plans throughout the 1930s and 1940s for what later became the Interstate Highway System. The general alignment for the highway that became I-40 was included in a plan released on August 2, 1947, by the Public Roads Administration of the now-defunct Federal Works Agency. The Interstate was officially authorized between Barstow and Greensboro by the Federal-Aid Highway Act of 1956, which created the Interstate Highway System. The numbering was subsequently approved by the American Association of State Highway Officials on August 14, 1957, along with most of the system.
In 1957, the California Department of Highways, the predecessor agency to the California Department of Transportation, proposed that the route be renumbered to I-30 instead because of the already existing US 40 in the state. This route was decommissioned in the state in 1964 as a part of a major revamping of California's overall highway numbering system. The California state government also submitted State Route 58 between Barstow and Bakersfield for I-40 extension potential in 1956 and 1968, but both of these requests were rejected.
From 1963 to 1966, the US government considered a plan, part of Project Plowshare, to use atomic bombs to excavate a path for I-40 through California. The project was canceled largely due to the cost of developing the explosives and due to the unavailability of a "clean bomb".