Wikipedia:WikiProject U.S. Roads/Illinois/All-time list

Given are the years of the first and last official maps the routes appear on (or when the route was legislated, in the case of SBI routes: original 1917 definitions, approved by voters in 1918; [http://www.idaillinois.org/cdm/compoundobject/collection/bb/id/29703 47-185 from 1923 (pp. 258-268)], approved in 1924). These are not always the exact years the routes were created or eliminated.