SR 172 begins at an
intersection with
SR 72, northeast of
Colbert, in Madison County. It heads northeast to an intersection with
SR 98, northwest of
Comer. It continues to the northeast and crosses over the
Broad River into Elbert County. In
Bowman is an intersection with
SR 17. Shortly afterward, SR 172 crosses into Hart County. It continues to the northeast until it meets its northern terminus, an intersection with
US 29/
SR 8/
SR 77 in
Hartwell.[1]