U.S. Route 80 or U.S. Highway 80 (US 80) is a major east–west United States Numbered Highway in the Southern United States, much of which was once part of the early auto trail known as the Dixie Overland Highway. As the "0" in the route number indicates, it was originally a cross-country route, from the Pacific Ocean to the Atlantic Ocean. Its original western terminus was at Historic US 101 in San Diego, California. However, the entire segment west of Dallas, Texas, has been decommissioned in favor of various Interstate Highways and state highways. Currently, the highway's western terminus is at an interchange with Interstate 30 (I-30) on the Dallas–Mesquite city line. Its eastern terminus is in Tybee Island, Georgia near the Atlantic Ocean.[3][self-published source?] Between Jonesville, Texas and Kewanee, Mississippi, US 80 runs parallel to or concurrently with Interstate 20. It also currently runs through Dallas, Texas; Shreveport, Louisiana; Jackson, Mississippi; Montgomery, Alabama; Columbus, Georgia; Macon, Georgia; and Savannah, Georgia.
Modern US 80 begins as a significant component of the urban freeway system of Dallas, Texas. With Spur 557, it serves as the shortest freeway route from the central and northern portions of Dallas to I-20, heading east towards Shreveport, Louisiana.
From its origin at I-30 in eastern Dallas, through its interchange with the I-635 "LBJ" Loop, to its junction with I-20 southwest of Terrell, US 80/Spur 557 is a full Interstate-grade, limited-access freeway. (This freeway was originally built as I-20 but was rerouted south of Dallas in 1971 and 1991.) In western Terrell, US 80 leaves the freeway, which continues southeast as (unsigned) Spur 557 to I-20, while US 80 runs north of I-20 through a number of small towns and cities, including Terrell, Mineola, Longview, and Marshall. It rejoins I-20 for about five miles (8.0 km), before splitting to pass through downtown Waskom before crossing into Louisiana.
US 80 is parallel to the newer I-20, which has supplanted it as a long-distance route, for the entirety of its length in Louisiana.
The highway crosses the state line from Texas into Caddo Parish as a two-lane road and crosses over to the south of I-20 without connecting with the freeway. It passes through the town of Greenwood where it meets US 79 coming north from Texas, and these two routes run concurrently eastward from there to Minden. US 79/US 80 crosses over I-20 again, this time at an interchange, and enters the city of Shreveport as Greenwood Road. The highway passes over I-220 without an interchange and continues east to an intersection with Jefferson Paige Road where it expands to four undivided lanes and enters the main part of the urbanized area. US 171 ends at US 79/US 80 at the intersection with Hearne Avenue. At this intersection, the road narrows to two through lanes. US 80 intersects I-20 again just east of here. At Mansfield Road (old US 171), the highway name changes to Texas Avenue and angles northeast through an industrial area. The road skirts the I-20/I-49 interchange and expands to four lanes for its final approach to downtown. At the west edge of downtown, eastbound jogs one block east on Crockett Street and two blocks north on Common Street north to Texas Street; westbound jogs one block south from Texas Street down Common to Texas Avenue. US 79/US 80 passes through downtown Shreveport on Texas Street before crossing the Red River on the 1930s vintage Long–Allen Bridge and entering Bossier City and Bossier Parish.
Through Bossier Parish, US 79/US 80 comprises a major urban and suburban arterial (East Texas Street) carrying a minimum of four lanes. In the eastern reaches of the parish, and continuing into Webster Parish, it is a divided highway. The road intersects the east end of I-220 at an interchange. US 79/US 80 stays to the north of I-20, except for a stretch east of Haughton where it strays to the south for a period, skirting the north edge of the Louisiana Army Ammunition Plant. At Dixie Inn, the highway intersects US 371. In Minden, US 79 separates from US 80 and continues its northeasterly trajectory toward Arkansas.
East of Minden, US 80 crosses to the south of I-20 and serves the Bienville Parish towns of Gibsland and Arcadia. Entering Lincoln Parish, the highway serves Simsboro and Grambling before entering Ruston (via West California Avenue) and overlapping US 167 on a north–south couplet of streets (Vienna Street/Trenton Street) through the business district. US 80 resumes its eastward path on the north side of Ruston and exits the city on East Georgia Avenue.
Between Ruston and Monroe the highway serves the small communities of Choudrant and Calhoun. Now on the north side of the interstate, it enters Ouachita Parish and approaches the Monroe area as a two-lane road. US 80 crosses Louisiana Highway 143 (LA 143) and enters West Monroe on Cypress Street, where it continues south into the business district and widens to a four-lane urban arterial. At junction LA 34 (B