Illinois 161 is an east-west route from I-57 through Centralia and Belleville to the Metro-East of St. Louis. It's not a very major route, but it is long.
Intersections from west to east:
IL159 at Swansea
It joins IL158 east near Belleville
IL158 breaks off
IL160 at New Baden
US51 in Centralia
I-57.
It passes through these towns: Swansea, Belleville, New Baden, Albers, Germantown, Bartelso, Hoffman, Centralia.
