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U.S. Route 278 (US 278) in the U.S. state of Georgia is an east–west United States Highway traversing the north-central portion of the state. The highway travels from its western terminus as US 278/SR 74 at the Alabama state line near Esom Hill to its eastern terminus at US 1/US 25/US 78/US 278/SC 121 in the Augusta metropolitan area where it crosses the Savannah River into South Carolina.
The route is concurrent with SR 6 from the Alabama state line to Lithia Springs, SR 100 and SR 1 in Cedartown, SR 8 from Lithia Springs to Decatur, SR 5 from Lithia Springs to Austell, and SR 10 from Atlanta to Avondale Estates, and again from Thomson to the South Carolina state line. It is entirely concurrent with SR 12 for 118 miles (190 km), and is briefly concurrent with the southern terminus of SR 124 in Lithonia.
Concurrencies of US 278 with US highways in Georgia include two long ones with its parent route US 78 from Lithia Springs to Druid Hills, and again from east of Thomson to the South Carolina state line. Others include US 19/US 41 in the vicinity of Georgia Tech in Atlanta, US 29 from Georgia Tech to Druid Hills, US 23 from the eastern part of Atlanta to Druid Hills, US 129/US 441 in the vicinity of Madison, US 1 from Augusta to the South Carolina state line, and US 25 from Augusta to the South Carolina state line.
It is also concurrent with I-20 from exit 75 in Lithonia until it reaches exit 90 in Covington in Newton County. US 278 largely travels parallel to I-20 from DeKalb County, near Atlanta, to McDuffie County.

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