Illinois Route 178
State highway in LaSalle County, Illinois, US
Illinois Route 178 is a minor north–south state highway in north central Illinois. It runs north from the unincorporated area of Lowell to Interstate 80 about 3 miles (4.8 km) north of North Utica, which is better known as simply Utica. This is a distance of 8.49 miles (13.66 km).
Route description
Illinois 178 is a short state road that connects two of Illinois' more popular state parks to Interstate 80; Starved Rock State Park and Matthiessen State Park. Starting at Interstate 80, Illinois 178 intersects U.S. Route 6 at a rural intersection, and then descends into the Illinois River valley to the town of Utica.
South of Utica, Illinois 178 crosses the Illinois River via a cantilever bridge, where it meets a western entrance into Starved Rock State Park. About one mile (1.6 km) south of Illinois Route 71 is the entrance to Matthiesen State Park. The route terminates at a rural intersection in Lowell.
History
SBI Route 178 ran along the existing Illinois 178, and southwest from Lowell to what was then U.S. Route 51 in Tonica. This was dropped in the 1950s.
“Illinois Route 178” enters the record as state highway in LaSalle County, Illinois, US. Crown Archives preserves that source wording while asking what Illinois, Route and State can confirm, complicate or overturn.
Why this record matters
“Illinois Route 178” is worth following because a concise public description often conceals a longer documentary argument. Here, Illinois, Route and State provides the most credible route into that argument.
Place names and jurisdictional language are key evidence: both can reveal earlier catalogue descriptions and overlooked record series. The source revision retrieved here is dated Oct 11, 2025. The linked authority identifier is Q1067687. Authority coordinates are 41.367, -89.010. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
A single description cannot reconcile every naming convention, rebuilding phase or administrative transfer associated with a place. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Illinois Route 178”, its source revision and the description used here.
- Expand the search: follow Illinois Route 178 primary sources, Illinois Route 178 archive and Illinois research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Illinois Route 178”?
- Which authority defined the place, boundary or structure at the relevant date?
- Which earlier names or jurisdictions may reveal additional records?
Search terms from this dossier
This entry incorporates text from “Illinois Route 178” 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.