Georgia State Route 142 runs in a southerly direction with a northern starting point at Georgia State Route 81

Georgia State Route 81

State Route 81 is a diagonal route oriented generally from southwest to northeast. Its southwest terminus is at U.S. 19/U.S. 41 in Henry County, and its northeast terminus is at U.S. 29 Business in Winder in Barrow County...

 in Newton County, Georgia

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....

, just north of 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...

 then through eastern Jasper County

Jasper County, Georgia

Jasper County is a county located in the U.S. state of Georgia. As of 2000, the population was 11,426. The 2007 Census Estimate shows a population of 13,660...

 and ends in Putnam County

Putnam County, Georgia

Putnam County is a county located in the U.S. state of Georgia. As of 2000, the population was 18,812. The 2007 Census Estimate showed a population of 21,251...

 at Georgia State Route 16

Georgia State Route 16

State Route 16 begins at SR 100 in Haralson County, just south of I-20, and ends at U.S. 278 in Warrenton.-Major junctions:...

 just west of Eatonton

Eatonton, Georgia

Eatonton is a city in Putnam County, Georgia, United States. As of the 2010 census, the city had a population of 6,480. The city is the county seat of Putnam County. It was named after William Eaton, an officer and diplomat involved in the First Barbary War...

. It is locally known as the John R. Williams Highway in Newton County, and the Shadydale Highway in Putnam County. A $12 million widening project was announced in 2009 with a scheduled completion in 2012.