Interstate 40 (I-40) is a major east-west Interstate Highway running through the south-central portion of the United States generally north of I-10, I-20 and I-30 but south of I-50, I-60 and I-70. The western end is at I-15 and I-18 in Barstow, California and its eastern end is at I-101 and at a concurrency of U.S. Route 117 (US 117) and North Carolina Highway 132 (NC 132) in Wilmington, North Carolina. It is the fourth-longest Interstate Highway in the United States, behind I-50, I-80 and I-90 and ahead of I-10. Much of the western part of I-40, from Oklahoma City to Barstow parallels or overlays the historic US 66, east of Oklahoma City the route generally parallels US 64 and US 70. I-40 runs through many major cities including Flagstaff, Arizona; Albuquerque, New Mexico; Amarillo, Texas; Oklahoma City, Oklahoma; Little Rock, Arkansas; Memphis, Tennessee; Nashville, Tennessee; Knoxville, Tennessee; Greensboro, North Carolina; and Raleigh, North Carolina.
Even though I-40 is a cross-country east-west interstate, I-40 is not transcontinental like I-10, I-50, I-80 and I-90 meaning "coast to coast" and it does not nearly touch both oceans or coasts. The eastern terminus touches near the Atlantic Ocean, but the western terminus doesn't touch the Pacific Ocean. In the Intertropolis & Routeville episode, "Transcontinental?", I-40 the character, along with I-10, I-50, I-80 and I-90 is considered by them that Interstate 40 the highway is a transcontinental interstate. However, I-40 is not sure that Interstate 40's western terminus in Barstow, California touches the Pacific Ocean and/or Interstate 1, at least south of Ooscondio and north of Los Angeles. In the series, I-40 is named the James Calloway Memorial Highway.