Illinois State Route 172 is a north, south, east, and west highway in Southeastern Whiteside County. It runs north-south from the Bureau/Whiteside County Line, northeast of Yorktown, to Star Road aprox. 9 miles north of Tampico. At Star Road, IL St Rt 172 turns and runs east-west. The northern end point is at IL St Rt 40. IL St Rt 172 passes through the following town in Whiteside County. Tampico
IL St Rt 172 is not multi-plexed in Whiteside County. IL St Rt 172 intersects the following highway in Whiteside County. Illinois State Route 40, near Rock Falls.
NB IL St Rt 172 at the Bureau/Whiteside County Line. A Whiteside County mile marker. NB IL St Rt 172 in Tampico. NB IL St Rt 172 north of Tampico. NB IL St Rt 172 southwest of Rock Falls. A guide marker on Star Road. NB IL St Rt 172 south of Rock Falls. A junction marker on SB IL St Rt 40. The northern end of IL St Rt 172. The northern end marker.
