^Northbound trailblazer seen by those leaving the junction of Ohio Route 325 and Ohio Route 588, April 2025.
Ohio State Route 325 runs mainly north-south across interior portions of Gallia and Meigs Counties. The unincorporated hamlet of Gage serves as the southern endpoint of Ohio Route 325, where this route meets Ohio Route 141. From here, Ohio Route 325 runs north through the hills of western Gallia County. It crosses US Route 35 at the town of Rio Grande. It then goes on to meet Ohio Route 160 at the village of Vinton (which oddly is not in Vinton County). As Ohio Route 325 exits Vinton, it begins curling toward the northeast, soon entering Meigs County. At the unincorporated hamlet of Hanesville, Ohio Route 325 ends oriented northeasterly, at Ohio Route 124. This terminus is about eight miles west of Pomeroy.