The route runs southwest-northeast through forested areas of the Pocono Mountains as a two-lane undivided road.

The route heads northbound as Warnertown Road, progressing around the shores of Lake Naomi.

After PA 423 leaves the shoreline, it turns northward and continues through the residential hills north of the lake.

There it turns eastward and returns northeastward for several miles and after several changes crosses Tobyhanna Creek and enters the community of Warnertown.

The road is renamed to Prospect Street and enters downtown Tobyhanna, crossing through a residential stretch.

The highway continues north of the tracks and along the side of the Army Depot into a rural portion of Tobyhanna.

After passing to the north of a large residential complex, the highway intersects with PA 196 in Gouldsboro.

The route passes a few stretches of residential homes and much woodland in Wayne County, turning to the northeast and intersecting with PA 191 in the community of South Sterling.

At this time, a small section northeast of Tobyhanna was paved while the remainder of the route was unpaved.