State Route 120 (SR 120) is a 90.7-mile-long (146.0 km) state highway that runs west-to-east through portions of Haralson, Paulding, Cobb, Fulton, and Gwinnett counties in northwestern part of the U.S. state of Georgia.

Haralson County is a county located in the northwestern part of the U.S. state of Georgia. As of the 2020 census, the population was 29,919, up from 28,780 in 2010. The county seat is Buchanan. The county was created on January 26, 1856, and was named for Hugh A. Haralson, a former Georgia congressman.