Illinois State Route 177 runs breifly in the southwestern corner of the county. It runs about five miles across Clinton County. IL St Rt 177 passes through the following town in Clinton County. New Memphis IL St Rt 177 is multi-plexed in Clinton County. Illinois State Route 160, from New Memphis to the Clinton/Washington County Line.
IL St Rt 177 intersects the following highway in Clinton County. Illinois State Route 160, at New Memphis.
SB IL St Rt 160/EB IL St Rt 177 in New Memphis. A junction marker on SB IL St Rt 160. SB IL St Rt 160/EB IL St Rt 177 near the Kaskaskia River. SB IL St Rt 160/EB IL St Rt 177 at the Clinton/Washington County Line.
