It is two-lane, undivided highway for most of its length with the exception of a four-lane stretch in Lambertville.

Route 179 extended to Lambertville and PA 179 was created in 1974 when the new US 202 freeway, running over the New Hope-Lambertville Toll Bridge, was completed.

PA 179 begins at an intersection with US 202 in Solebury Township, Bucks County, Pennsylvania, heading east on two-lane undivided West Bridge Street through commercial areas.

Farther east, the route gains a center left-turn lane and enters more residential surroundings as it passes New Hope-Solebury High School.

[3][4] At the middle of the New Hope-Lambertville Bridge, the road enters the city of Lambertville in Hunterdon County, New Jersey and becomes Route 179.

[14] The new US 202 freeway between the New Hope-Lambertville Toll Bridge and Route 179 southwest of Ringoes was completed in October 1974.

As a result, Route 179 was extended along the old US 202 alignment to the state line in Lambertville and PA 179 was designated along the former US 202 through New Hope.