The route is a two-lane undivided road that runs through rural areas in the northern part of Wayne County.

The southern portion of the route follows the Bethany and Honesdale Turnpike chartered in 1831 while the section north of Pleasant Mount follows the Belmont and Easton Turnpike, which continued south to Easton, which was chartered in 1812 and completed in 1820.

The road heads through wooded areas with some homes, crossing into Dyberry Township.

Here, the route becomes Bethany Turnpike and continues through more wooded areas with some fields and residences, turning north.

PA 670 enters the borough of Bethany, where it becomes Wayne Street and passes homes, turning northwest.

The route turns northwest and runs through more rural areas, crossing into Mount Pleasant Township and coming to an intersection with PA 247.

[2][3] The section of PA 670 north of PA 371 follows part of the alignment of the Belmont and Easton Turnpike, a turnpike that was chartered on March 15, 1812 to run along the North and South road between the Easton and Wilkes-Barre Turnpike in Northampton County and the community of Belmont in Mount Pleasant Township, Wayne County.