The southern terminus of SR 251 is located at an intersection with
US 31 opposite Pryor Street in
Athens. After crossing
I-65 via
overpass and exiting the Athens city limits, the route proceeds primarily northeasterly through several unincorporated communities before entering the city limits of Ardmore. The northern terminus is located at an intersection with
SR 53 running concurrently with 6th Street. At its northern terminus, SR 251 reverts to Ardmore Avenue, which picks up SR 53. ==History==