Illinois 29 runs near the right bank (going down stream) which is (north and west) of the Illinois River from Spring Valley to Peoria. Starting at U.S. 6/Illinois 89 at the north edge of Spring Valley, the road passes through the small towns of Putnam and Henry, intersecting Illinois Route 18 at Henry. In Sparland, Illinois 29 intersects Illinois Route 17. It then runs beneath the bluff at Hopewell before becoming 4th Street, the main north–south artery through Chillicothe.
In East Peoria, Route 29 splits from Interstate 74 and proceeds south, entering Creve Coeur on Main Street and providing an interchange with Interstate 474. It enters Pekin as 8th Street and forks off as 5th Street before a short concurrency with Illinois Route 9 near the Pekin Bridge. Splitting onto 2nd Street (southbound) and 3rd Street (northbound) before crossing the bridge, Route 29 exits Pekin as 2nd Street, passing the Federal Correctional Institution, Pekin, and from there goes substantially directly south through Mason City to Springfield.
Route 29 was established in 1918, and ran from DePue to Peoria. It was extended twice over Illinois Route 24 in 1936 and 1940, and in 1942 replaced an old alignment of U.S. Route 6 from Bureau Junction to Spring Valley.[2]
The routing of Route 29 through Peoria was changed in 2012. That same year, U.S. Route 24 was rerouted over the river along a more southwestern alignment. 29 was relocated from the Cedar Street Bridge to the Murray Baker Bridge, which carries Interstate 74.
US 51 / IL 16 in Pana
I-55 / I-72 / US 36 in Springfield
US 136 in Mason City
I-474 / US 24 in Creve Coeur
US 150 / IL 8 in East Peoria
I-74 in East Peoria
I-180 / IL 26 in Princeton
US 6 / IL 89 in Spring Valley
