Illinois State Route 110
The current Illinois Route 110 is the Chicago to Kansas City (CKC) highway that meanders from Chicago to Quincy in Illinois. The designation was created in 2010 by the Illinois General Assembly. Illinois 110 runs concurrently to other routes for its entire distance including all of I-88, I-172, and Illinois 336. CKC is marked in Missouri along US 36 and I-35.
The original routing of Illinois 110 went from Freeburg to near Addiesville on a stretch that is currently part of Illinois 15. This designation existed in the 1930s through the 1940s.