SR 190 begins at an intersection with US 27/SR 1, south of Pine Mountain, in Harris County.

After leaving the park, it enters Meriwether County and Roosevelt's Little White House Historic Site, just north of Dowdell's Knob.

It heads northeast until it meets its eastern terminus, an intersection with SR 41/SR 85 (Broad Street).

On top of the mountain, SR 190 passes over State Route 354 on a historic bridge built by the Civilian Conservation Corps.

Until the mid-1980s, SR 190 ran through Manchester eastwards to Chalybeate Springs, Georgia with a planned extension of the highway across the Flint River to an eastern terminus at U.S. 19 north of Thomaston, GA.