U.S. Route 79 (US 79) enters Kentucky from Tennessee in Todd County west of Guthrie and runs northeast into Logan County, terminating at a junction with US 68, US 68 Business, and Kentucky Route 80 (KY 80) in Russellville.

The route continues to the northeast, passing north of Guthrie and Allensville in rural areas of Todd County.

10.606 miles (17.069 km) from the Kentucky-Tennessee border, US 79 crosses into Logan County where it becomes known as Clarksville Road.

US 79 ends at an intersection with Bowling Green Road which carries US 68 and KY 80 to the east and US 68 Bus.

[7] A historical marker was erected at the eastern terminus in 2019 commemorating the importance of the highway's impact on early economical development in western Kentucky.