The highway heads northeast, through hilly regions before reaching the northern terminus at Interstate 70 (I-70) in Union Township.

I-70 continues north to get to the Pennsylvania Turnpike, and south to pass into Maryland.

[2] After passing through a small wooded area, PA 731 comes to another intersection with McKees Gap Road, at which point it makes a right turn.

[3] The route was around 4 miles long and included some of the larger, unmarked roads in the area.

[5] In August 2009, the Pennsylvania Department of Transportation completed reconstruction of the interchange with I-70.