State Route 12 begins in Avondale Estates

Avondale Estates, Georgia

Avondale Estates is a city in DeKalb County, Georgia, United States. The population was 2,960 at the 2010 census.Avondale Estates was founded in 1924 by George Francis Willis, who purchased the entire village of Ingleside to create a planned community. The city was named after Stratford-upon-Avon,...

, DeKalb County, Georgia

DeKalb County, Georgia

DeKalb County is a county located in the U.S. state of Georgia. The population of the county was 691,893 at the 2010 census. Its county seat is the city of Decatur. It is bordered to the west by Fulton County and contains roughly 10% of the city of Atlanta...

 at its intersection with SR 10 and ends at SR 10/US 78

U.S. Route 78

U.S. Highway 78 is an east–west United States highway that runs for 715 miles from Memphis, Tennessee, to Charleston, South Carolina. Between Memphis and Birmingham, Alabama, it is being upgraded to become Interstate 22....

 in Thomson, Georgia

Thomson, Georgia

Thomson, incorporated February 15, 1854, is a city in McDuffie County, Georgia, United States. The population was 6,828 at the 2000 census. The city is the county seat of McDuffie County. Thomson's nickname is "The Camellia City of the South", in honor of the thousands of camellia plants...

. State Route 12 overlaps U.S. Route 278

U.S. Route 278

U.S. Route 278 is a parallel route of U.S. Route 78. It currently runs for 1,074 miles from Hilton Head Island, South Carolina to Wickes, Arkansas at U.S. Highway 71/U.S. Highway 59. It might be notable that it is longer than its parent highway, US Hwy-78. US Hwy-278 passes through the states of...

 its entire length. It is also concurrent with Interstate 20

Interstate 20 in Georgia

In Georgia, Interstate 20 runs from the Alabama border to the Savannah River, which the Georgia-South Carolina border straddles. It passes through the heavily congested Atlanta metropolitan area and exits the state at Augusta...

/SR 402 from Exit 75, which is SR 124 (Turner Hill Road) in Lithonia

Lithonia, Georgia

Lithonia is a suburban town in eastern DeKalb County, Georgia, incorporated as a city. Lithonia's population was 1,924 at the 2010 census.-Geography:...

  until it reaches Exit 90 in Covington

Covington, Georgia

Covington is a city in Newton County, Georgia, United States. As of the 2010 census, the city had a population of 13,118. The city is the county seat of Newton County...

 in Newton County

Newton County, Georgia

Newton County is a county located in the U.S. state of Georgia. As of 2000, the population was 62,001. The 2010 Census showed a population of 99,958. The county seat is Covington....

. State Route 12 largely runs parallel to Interstate 20 from DeKalb County, near Atlanta, to McDuffie County

McDuffie County, Georgia

McDuffie County is a county located in the U.S. state of Georgia. It was created on October 18, 1870. As of 2000, the population was 21,231. The 2007 Census Estimate showed a population of 21,551. The county seat is Thomson....

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