 SR 678 provides a shorter alternative for traffic using SR 374 en route from Hocking Hills State Park up to U.S. Route 33 (US 33) at Rockbridge, in conjunction with SR 180.State Route 678 begins at a T-intersection with SR 374 in Hocking County's Laurel Township.Starting out, the highway weaves its way in a northerly and easterly fashion, passing primarily through a forested landscape, with spaces of open grass and the occasional home also appearing alongside the highway.