Interstate 24
Interstate 24 is an Interstate Highway in the Midwestern and Southeastern United States. It runs diagonally from I-57, 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.
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 southeast of the city and is considered the most congested stretch of highway in the state. The stretch through Chattanooga also experiences severe congestion, due to an unusually high volume of truck traffic. 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 to its present-day western terminus in Pulleys Mill, Illinois, in 1964. As a result, I-24 was the last mainline Interstate Highway in Tennessee and Kentucky to be completed, with the last sections in the two states opening in 1978 and 1980, respectively.
Route description
Illinois
I-24 begins at exit 44 on I-57 in southern Williamson County, near the community of Pulleys Mill. The highway heads southeast into rural Johnson County, bypassing Goreville to the east. It reaches an exit at Tunnel Hill Road, which serves Goreville and Tunnel Hill. The highway continues south to its next exit at US Route 45 north of Vienna. It reaches its next exit at Illinois Route 146 in eastern Vienna. I-24 heads southeast from Vienna into Massac County. Its first exit in Massac County is at Big Bay Road, which serves the communities of Big Bay and New Columbia. I-24 continues southward, bypassing the community of Round Knob before entering Metropolis. The highway meets US 45 again in Metropolis and passes west of Fort Massac State Park. It leaves Metropolis and crosses the I-24 Bridge over the Ohio River. After that, it continues into Kentucky.Kentucky
I-24 enters the Jackson Purchase region of western Kentucky on a north–south alignment. Immediately within McCracken County, the route begins gradually veering southeast and enters the western fringes of Paducah a few miles later. The welcome center in Paducah utilizes Whitehaven, the only historic house in the United States used as a rest area. In Paducah, the Interstate continues to shift southeast and has interchanges with US 60, US 62, and US 45. Passing through the Hendron and Farley communities adjacent to Paducah, the highway shifts into a direct east–west alignment several miles later and has an interchange with US 68 in Reidland. The route then enters Marshall County and, about later, reaches an interchange with I-69 and a connector road to US 62 and Calvert City to the north. Here, it begins a concurrency with the former. The two Interstates then shift northeast and have an interchange with US 62 about later. A short distance later, the Interstates cross the Tennessee River onto the Pennyroyal Plateau and Livingston County just north of Kentucky Dam and its Kentucky Lake impoundment. The highways then have an interchange with Kentucky Route 453 north of Lake City and Land Between the Lakes National Recreation Area. They then cross the Cumberland River about later into Lyon County a few miles north of Barkley Dam and Lake Barkley.Gradually veering eastward, the two Interstates reach US 62 again near Kuttawa and Eddyville. Less than later, I-69 splits off to the northeast at a trumpet interchange, and I-24 passes through Mineral Mound State Park, veering southeast a few miles later. Passing through a mostly wooded area, the Interstate crosses KY 93 without an interchange, and then has an interchange with KY 293 near the Kentucky State Penitentiary. It then crosses an inlet of Lake Barkley a few miles later. Some distance later, the freeway enters a landscape consisting mostly of farmland and dips briefly into the southern tip of Caldwell County, where it has an interchange with KY 139. The Interstate then enters Trigg County and crosses the Muddy Fork Little River a short distance later. About later, the Interstate has an interchange with US 68 and KY 80 between Cadiz and Hopkinsville. The highway then crosses into Christian County a few miles later. Passing over the next several miles through additional farmland and bypassing Hopkinsville to the southwest, the Interstate reaches the southern terminus of I-169 at a trumpet interchange. About later, the Interstate has a partial cloverleaf interchange with US 41 Alternate, which provides access to Hopkinsville to the north and Fort Campbell and Clarksville, Tennessee, to the south. I-24 then crosses into Tennessee about later.
Tennessee
Clarksville and Western Highland Rim
I-24 crosses into Tennessee from Kentucky traveling in a southeasterly-to-northwesterly direction into Montgomery County and serving as a major means of access to St. Louis and Chicago to the northwest. Immediately within the eastern outskirts of Clarksville, the fifth-largest city in Tennessee, the Interstate reaches an interchange with State Route 48, less than later, which provides access to Trenton in Kentucky to the north. About later the Interstate reaches US 79, which also provides access to Guthrie and Russellville in Kentucky to the northeast. Bypassing Clarksville to the east, the Interstate next reaches SR 237. The highway then begins a steep descent, with the westbound lanes utilizing a truck climbing lane to ascend the grade from the east. It then crosses the Red River before reaching SR 76.Leaving Clarksville, the highway enters a long straight section with several steep grades and crosses into Robertson County a short distance later. Several miles later, the Interstate reaches an interchange with SR 49 near Pleasant View and Coopertown, which provides access to Springfield to the northeast and Ashland City to the southwest. The route then descends, utilizing another westbound truck lane, before briefly entering Cheatham County. The Interstate then crosses another steep hill over the next several miles, utilizing an eastbound truck lane before crossing into Davidson County. It then has an interchange with US 431 near the Joelton community and begins a gradual descent into the Nashville Basin, containing a westbound truck lane. Passing over the next few miles through dense woodlands, the highway reaches SR 45 about later. Over the next beyond this point, the Interstate crosses over another steep hill, utilizing truck lanes on both the eastbound and westbound ascent before reaching Nashville at SR 155.
Nashville metropolitan area
Entering Nashville, I-24 has a cloverleaf interchange with SR 155, a northern controlled-access beltway around Nashville. Less than later, the Interstate joins a concurrency with I-65, where the combined routes carry eight throughlanes and travel due south. About later is an interchange with US 41A/US 431. About beyond this point, I-65 splits off and I-24 passes along the east side of downtown Nashville, where it reduces to six lanes and has interchanges with US 41, US 431, and US 31E, and passes near Nissan Stadium. The interstate then crosses the Cumberland River on the Silliman Evans Bridge and joins in a concurrency with I-40, traveling southeast-to-northwest with eight throughlanes. later, I-40 splits off eastwardly, heading toward Knoxville. Located at this interchange is also a partial interchange with US 41/US 70S.Less than later is an interchange with the eastern terminus of I-440, which is also accessible from I-40 nearby. Between I-40 and I-440, I-24's eastbound lanes are split into two barrier-separated carriageways to prevent weaving of traffic destined from I-40 to I-440. A short distance later is once again an interchange with SR 155 near Nashville International Airport. Beginning at the next exit, SR 255, the left lanes operate as high-occupancy vehicle lanes during rush hour. Over the next few miles, I-24 passes through the Antioch neighborhood, where it has interchanges with Haywood Lane and SR 254, and crosses Mill Creek. I-24 then continues through southeast Nashville, reaching interchanges with Hickory Hollow Parkway and SR 171.
Continuing through the southeastern suburbs of Nashville, I-24 crosses into Rutherford County about beyond. Immediately within the city of La Vergne, the Interstate has an exit with a connector road to that city. It then enters Smyrna where it first has an interchange with SR 266. The Interstate then enters a long straightaway and reaches an interchange with SR 102, which also serves Smyrna and the Nissan Smyrna Assembly Plant. Leaving Smyrna, the route enters an unincorporated urban area, before reaching a three-level interchange with I-840, the outer southern beltway around Nashville. I-24 then enters Murfreesboro, the largest suburb of Nashville and sixth-largest city in Tennessee. The Interstate first has an interchange with a local thoroughfare, before reaching SR 96, which also connects to Franklin. A short distance later, the Interstate crosses the west fork of the Stones River and reaches SR 99. A short distance later, the highway reaches US 231, which also connects to Lebanon and Shelbyville. Here, the HOV lane restriction terminates, and the Interstate reduces from eight to four lanes. Leaving Murfreesboro, the Interstate later has an interchange with the Joe B. Jackson Parkway, which serves as an outer beltway around southeast Murfreesboro.