Illinois Route 172
State highway in northwestern Illinois, US
Illinois Route 172 is an inverted-L-shaped highway in northwestern Illinois, though it is marked as being a north–south highway on signage. It runs from Illinois Route 40 to Illinois Route 92 by way of Tampico. This is a distance of 13.06 miles (21.02 km). Illinois 172 is also a part of the Ronald Reagan Trail.
Route description
Illinois 172 runs north from Illinois 92 through Tampico. It then runs east over a feeder for the Hennepin Canal to Illinois 40. Illinois 172 is a two-lane surface road for its entire length. It is known as Main Street through Tampico, Tampico Road around Tampico, and Star Road for the east–west portion.
History
SBI Route 172 originally ran from Libertyville to Gurnee; this became Illinois Route 63, and then Illinois Route 21. In 1946, Illinois 172 was used on former Illinois Route 226, which in addition to its current route ran west to Prophetstown, forming a T-shaped route.
This brief starts where responsible research should: with the source description of “Illinois Route 172” as state highway in northwestern Illinois, US. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as state highway in northwestern Illinois, US. Its deeper value depends on whether names, dates, institutions and citations support that framing.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Apr 22, 2025. The linked authority identifier is Q1057541. Authority coordinates are 41.628, -89.786. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1946.
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This entry incorporates text from “Illinois Route 172” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.