SC 191 travels to the north-northwest and immediately crosses over a railroad track and the Sand River, and has an interchange with U.S. Route 1 (US 1) and US 78 (Jefferson Davis Highway) on the border of Warrenville and Graniteville.

The highway parallels Flat Rock Pond and Horse Creek.

Then, it passes a U.S. Post Office branch on the southeastern edge of Vaucluse Pond.

In a rural part of the county, it intersects SC 19 (Edgefield Highway).

The highway continues traveling through rural areas and crosses over Hall Branch before it meets its northern terminus, an intersection with SC 121, in the extreme southern part of Johnston.