April 20, 2008: North end of I-172 in no place in particular, Illinois. Functionally, I-172 is a big bypass of Quincy and connection for Quincy to points southwest and southeast, but now it works for the northeast as well with progress on the IL 336 corridor. It’s part of the Chicago-Kansas City corridor, a name pushed as an attempt to get truck traffic to use I-88 to the Quad Cities and a series of four-lane roads south of there to Hannibal, then US 36 (future I-72) and I-35 to KC. Illinois has also given the route a designation of IL 110, which like IA 27 is redundant for a good portion of the route.
So…why Keokuk? IL 96 goes to Hamilton, across the river from Keokuk, and IL 96 isn’t at this intersection — it’s to the west — so that’s three separate routes one must take from this location to get there. I won’t complain too much, though, since Missouri has the exact opposite problem of not mentioning Keokuk on US 61 until it absolutely has to!
Keokuk and Mount Sterling are the control cities for the entire length of I-172 except the south end itself. Compare, for example, this sign at an interchange with I-39. Mount Sterling is east on US 24.
(You thought I would go with the obvious choice for this number, didn’t you? Ha!)