State Route 315, known locally as the Olentangy Freeway, running almost parallel to Olentangy River Road for most of its length,[3] is a north–south highway in central Ohio, in the Columbus metropolitan area.

The controlled access section carries two or three lanes in each direction, depending on the location.

The route passes through Ohio State University campus.

[4] An unsigned State Route 315C exists which begins on the Interstate 670 westbound ramp to Neil Avenue, follows Neil south to the Goodale-Neil Connector and Goodale Avenue, then up Olentangy River Road and onto the ramp to State Route 315 southbound, where it ends.

It is clear from the Straight Line Diagram that SR 315C exists westbound only.