U.S. Route 78

U.S. Route 78 (US 78) is an east–west United States Numbered Highway that runs for 843.3 mi from Cash, Arkansas to Charleston, South Carolina. From Byhalia, Mississippi to Birmingham, Alabama, US 78 runs concurrently with Interstate 22 (I-22). The highway’s western terminus is at US 67 (Future I-57)/Arkansas Highway 226 (AR 226) near Cash and its eastern terminus is on Line Street, in Charleston. Prior to November 2023, before the western extension, the highway's former western terminus was at US 64/US 70/US 79 (Second Street) in Memphis, Tennessee.

Route description
!AR !TN !MS !AL !GA !SC !Total
 * 140.8 mi
 * 15.0 mi
 * 118.0 mi
 * 194.0 mi
 * 233.3 mi
 * 142.2 mi
 * -class=sortbottom style="border-top: 2px solid #a2a9b1;"
 * 843.3 mi
 * }

Arkansas
US 78 begins at interchange with US 67 (Future I-57) at exit 102 where the roadway continues as AR 226 west toward Swifton, Arkansas. The route goes through towns of Cash, Jonesboro, Lake City, Black Oak, Monette, Manila, Blytheville, Marion, and West Memphis before crossing on the Memphis & Arkansas Bridge over the Mississippi River to enter Tennessee in Memphis.

Tennessee
US 78 enters Tennessee along Interstate 55 from Arkansas and shortly after diverges from I-55 onto E.H. Crump Boulevard. It is concurrent with US 61, US 64, US 70, US 79 and SR 1 until Third Street/B.B. King Boulevard. US 61 turns south onto SR 14 (Third Street) at this intersection. US 64, US 70, US 79 and SR 1 turn north onto SR 4 (Danny Thomas Boulevard), while southbound SR 4 becomes concurrent with US 78 and continues along E.H. Crump Boulevard. Around I-240, the road changes names to Lamar Avenue and continues southeastwardly to the Mississippi state line.

Before the extension of this roadway into Arkansas, US 78 ran along MLK Avenue (formerly Linden Street) and Somerville Street until E. H. Crump Boulevard, turning onto Lamar Avenue. This former portion of US 78 was overlapped in its entirety by State Route 278 (SR 278).

In Memphis, US 78 is historically known as Pigeon Roost Road, and some aborted sections of the highway in Mississippi also claim that name as well as Lamar Avenue.

Mississippi
US 78 is a freeway for its entire length in Mississippi. The section from its intersection with Interstate 269 in Byhalia, Mississippi to the Alabama state line is concurrent with Interstate 22. The highway runs across the northeastern rural part of the state, connecting several population centers. Mississippi's portion of US 78 is defined in Mississippi Code Annotated § 65-3-3. The old routing of US 78 through the state is signed as MS 178.

Alabama
US 78 is a major east–west U.S. highway across the central part of Alabama. It is internally designated State Route 4 (SR 4) by the Alabama Department of Transportation, though the only section of State Route 4 that is signed is along portions mainly west of Jasper. The section from the Mississippi state line to near Graysville is concurrent with Interstate 22; from Graysville south to Birmingham, US 78 takes its original routing. East of Birmingham to the Georgia state line, US 78 has been replaced as a major through-route by Interstate 20. The two routes roughly parallel each other, with junctions at Leeds and Pell City.

West of Jasper, old US 78 is signed as AL 118 to Guin, and the segment from Guin northward to I-22 at Hamilton is signed as US 43/US 278.

Georgia
US 78 enters Georgia in Haralson County, and then proceeds through Carroll County and Douglas County. In Douglasville, located in Douglas County, US 78 runs through the downtown, historical part of the city. It is the original thoroughfare for these Georgia counties.

The route then continues eastward through Cobb and Fulton counties into Atlanta. After crossing Peachtree Street, where US 78 marks a boundary between downtown and Midtown, US 78 is largely conterminous with Ponce de Leon Avenue. As it proceeds due east, this section of the route passes Ponce City Market and crosses the Eastside Trail of the BeltLine before skirting a number of Frederick Law Olmsted-designed parks in the Druid Hills Historic District at the eastern edge of the city.

After entering Decatur in DeKalb County, US 78 departs from Ponce de Leon Avenue to head northeast. South of the site of North DeKalb Mall, another short freeway portion begins — leading from just inside the eastern rim of Interstate 285 (the Perimeter) to the suburbs of Clarkston, Tucker, Stone Mountain, and Snellville. This portion is named the Stone Mountain Freeway, and provides an excellent view of Stone Mountain for eastbound motorists.

The route then proceeds east across Gwinnett, Walton, and Oconee counties. In Oconee County, US 78 leaves Moina Michael Highway at the SR 316 interchange, turning right and running concurrent with SR 316/US 29. (From this point, Moina Michael Highway is signed as US 78 Business, which follows the original route of US 78 through Athens, Ga.) At the terminal eastern interchange of SR 316 both US 78 and US 29 turn right and join with SR 10 Loop, a mostly interstate-grade bypass that rings Athens-Clarke County. US 78 exits the bypass and turns right at the Lexington Road interchange. From there US 78 passes through Oglethorpe, Wilkes, McDuffie and Columbia Counties into Augusta and then onto one of the twin bridges across the Savannah River into South Carolina.

South Carolina
US 78 provides the most direct route between Augusta and Charleston, through the South Carolina Lowcountry. Crossing Savannah River into the state, it goes northeast into Aiken before going southeasterly through the cities and towns of Williston, Blackville, Denmark, Bamberg, Branchville, and St. George. East of Dorchester, it parallels Interstate 26 into downtown Charleston, where it ends.

History
In western Alabama, the historical name of US 78 is Bankhead Highway. It is also known by this name in portions of Georgia, including Atlanta, and the Bankhead neighborhood takes its name from that stretch of road. Also, the old section of US 78 (now MS 178) that travels through downtown New Albany, Mississippi, is named Bankhead Street.

Throughout the 2000s, US 78 has been gradually upgraded into a four-lane freeway in Mississippi and Alabama and signed as I-22. US 78 is concurrent with I-22 from Byhalia, Mississippi to just outside of Birmingham, Alabama, only branching off just outside of Graysville, Alabama with I-22 traveling about 11 mi eastward to its terminus at I-65.

On October 25, 2023, the Arkansas Highway Commission voted unanimously to extend the US 78 designation into Northeast Arkansas. According to the Arkansas Department of Transportation (ARDOT), the US 78 designation would be extended along several other routes from its current western terminus in Memphis, Tennessee across the Memphis & Arkansas Bridge to a new western terminus near Cash, Arkansas at US 67 (Future I-57). The route would be cosigned along portions of US 64, US 70, US 79, I-55, US 61, I-40, Arkansas Highway 18 (AR 18), AR 18S, I-555, US 49, US 63, and AR 226. This extension of the US 78 route designation was seen as a way to boost economic growth in the region by assigning a single route number for travelers to follow. The extension was approved by the AASHTO in November 2023.

Future
US 78 and SR 4 in Memphis, Tennessee is currently being upgraded between the Mississippi state line and SR 176, a distance of about 5.1 mi. The route, Lamar Avenue, sees heavy freight traffic and has "crippling congestion." The work includes expanding the road from four to six lanes, adding three new interchanges, and upgrading additional ones. The work is being done in three segments with the first one starting in 2018.

Major intersections

 * Arkansas
 * near Cash
 * west of Jonesboro. The highways travel concurrently toward and through Jonesboro.
 * in Jonesboro. The highway travels through Jonesboro.
 * in Blytheville
 * in Blytheville. Begin I-55 concurrency.
 * in Blytheville
 * northwest of Turrell. Begin US 61 concurrency.
 * in Marion. Begin US 64 concurrency.
 * in West Memphis. I-40 travels through West Memphis. Begin US 79 concurrency.
 * in West Memphis. Begin US 70 concurrency.


 * Tennessee
 * in Memphis. End I-55 concurrency.
 * in Memphis. End US 61/US 64/US 70/US 79 concurrency.
 * in Memphis
 * in Memphis
 * in Memphis


 * Mississippi
 * west-northwest of Byhalia. Begin I-22 concurrency.
 * in Tupelo


 * Alabama
 * in Hamilton
 * near Adamsville
 * near Birmingham. End I-22 concurrency.
 * in Birmingham
 * in Birmingham. The highways travel concurrently through Birmingham.
 * in Birmingham
 * in Leeds
 * in Leeds
 * northwest of Chulavista. The highways travel concurrently to Pell City.
 * in Pell City
 * in Riverside
 * in Oxford.


 * Georgia
 * in Bremen
 * in Lithia Springs. The highways travel concurrently to Druid Hills.
 * in Atlanta
 * in Atlanta. The highways travel concurrently through Atlanta.
 * in Atlanta. US 29/US 78 travels concurrently to the Scottdale–North Decatur city line.
 * in Atlanta. The highways travel concurrently to Decatur.
 * on the Scottdale–Clarkston city line
 * southeast of Bogart. The highways travel concurrently to Athens.
 * in Athens. The highways travel concurrently through Athens.
 * in Washington
 * southeast of Thomson. The highways travel concurrently to Clearwater, South Carolina.
 * in Harlem
 * in Augusta
 * in Augusta. The highways travel concurrently to Aiken, South Carolina.
 * in Augusta. The highways travel concurrently to North Augusta, South Carolina.


 * South Carolina
 * in North Augusta
 * in Denmark
 * in Bamberg
 * in Branchville. The highways travel concurrently through Branchville.
 * in St. George
 * in St. George
 * east of Dorchester
 * in North Charleston
 * in North Charleston. The highways travel concurrently through North Charleston.
 * in North Charleston
 * in North Charleston
 * King Street/Line Street in Charleston

Related U.S. Routes

 * U.S. Route 178
 * U.S. Route 278
 * U.S. Route 378