Interstate 24

Interstate 24 (I-24) is an Interstate Highway in the Midwestern and Southeastern United States. It runs diagonally from I-57, 10 miles (16 km) south of Marion, Illinois, to Chattanooga, Tennessee, at I-75. It travels through Illinois, Kentucky, Tennessee, and Georgia. As an even-numbered Interstate, it is signed as an east–west route, though the route follows a more southeast–northwest routing, passing through Nashville, Tennessee. The numbering deviates from the standard Interstate Highway System grid, lying further north than its number would indicate west of Nashville. The short segment within Georgia bears the unsigned designation State Route 409 (SR 409). I-24 between Nashville and Chattanooga is part of a longer north–south freight corridor which runs between Chicago and Atlanta. The Interstate has facilitated the rapid growth of the largest suburban corridor in the Nashville metropolitan area, which runs for more than 30 miles (48 km) southeast of the city and is considered the most congested stretch of highway in the state. The first express toll lanes in Tennessee are planned to be constructed on this stretch. The stretch through Chattanooga also experiences severe congestion, due to an unusually high volume of truck traffic combined with the mountainous geography. The stretch of I-24 across the Cumberland Plateau, commonly known as "Monteagle Mountain", is considered one of the most hazardous stretches of highway in the US, particularly for trucks, due to its steep descents, which measure a maximum of six-percent grade. As proposed by the Federal-Aid Highway Act of 1956, the western terminus of I-24 was originally located in Nashville. Most of the route between Nashville and Chattanooga was constructed in the 1960s, with the final section opening in 1971. After extensive lobbying from local politicians, the Bureau of Public Roads, the predecessor agency to the Federal Highway Administration, authorized an extension of I-24...