Route 173 begins at an intersection with Route 76 in Cape Fair, Stone County, heading north on a two-lane undivided road.
The road passes through wooded areas with some homes, curving to the northwest.
Route 173 passes through more forests, curving northwest before heading north through a mix of fields and woods with occasional residences.
Farther north, the road comes to an intersection with Route 248.
The route continues through more rural areas, turning northeast and crossing Missouri and Northern Arkansas Railroad's Aurora Subdivision.