PA 491 begins at an intersection with US 202 in Concord Township, Delaware County, heading east-southeast on two-lane undivided Naamans Creek Road.

The route passes through residential areas, crossing into Bethel Township at the Pyle Road intersection.

Upon reaching the community of Ogden, PA 491 turns to the southeast as it crosses CSX's Philadelphia Subdivision railroad line at-grade.

After crossing into Lower Chichester Township, the route passes under I-95 as it heads south into woodland to the Delaware border.

A short distance past the state line, the road passes an entrance to the former Tri-State Mall and the intersection with residential Woodfield Drive.