In St. Clair County, Illinois State Route runs from the Monroe/St. Clair County Line near Columbia to Scott Air Force Base/Mid-America Airport. This is the direct route to Belleville from Columbia. IL St Rt 158 passes through the following towns in St. Clair County. Millstadt
The eastern end of IL St Rt 158 near O'Fallon. The eastern end marker. EB U.S. Rt. 50/IL St Rt 158 near O'Fallon. A BGS on EB I-64/U.S. Rt. 50. Another BGS on EB I-64/U.S. Rt. 50. A BGS on SB IL St Rt 158. WB IL St Rt 158 south of I-64/U.S. Rt. 50. A junction marker on SB IL St Rt 158/EB IL St Rt 161. EB IL St Rt 158/177 east of Belleville. A junction marker on SB Greemount Road. EB IL St Rt 158/177 in Belleville. A junction marker on NB IL St Rt 159. EB IL St Rt 13/158 west of Illinois Ave. EB IL St Rt 13/158 neear St Clair Ave in Belleville. A BGS over WB IL St Rt 15. A BGS on WB IL St Rt 15. A BGS on EB IL St Rt 15. Anothern BGS on EB IL St Rt 15. WB IL St Rt 158 west of IL St Rt 15. A junction marker on IL St Rt 163. WB IL St Rt 158 near the Monroe/St. Clair County Line. A St. Clair County mile marker.
