U.S. Route 45 (US 45) in the state of Illinois is a major north–south U.S. Highway that runs from the Brookport Bridge over the Ohio River at Brookport north through rural sections of eastern Illinois and then through the suburbs of Chicago to the Wisconsin state line east of Antioch. This is a distance of 428.99 miles (690.39 km).[1] US 45 is the longest numbered route in Illinois.
The route crosses the Ohio River over the Brookport Bridge, and then curves to the west to travel through downtown Metropolis. It continues northwest to Vienna, after which it turns to the northeast.
US 45 north of IL 141
Champaign/Urbana
US 45 serves as the western boundary of the University of Illinois at Urbana–Champaign campus. Entering downtown Champaign as Neil Street, US 45 then goes east on Springfield Avenue, running concurrently with US 150. Farther east of downtown Champaign, it again serves as a boundary for the campus. Following Wright Street, US 45 then moves east on University Avenue, forming the northern border of the University. This path continues to Cunningham Avenue in Urbana. US 45 then turns onto Cunningham Avenue northward towards Chicago.
Starting at 95th Street near Hickory Hills, US 45 becomes concurrent US 12 and US 20. Two miles further north, at Archer, the road loses its 96th Avenue designation; this is due to the road entering suburbs that do not use Chicago's address system, and that most of its alignment north of Archer would be at 10000 W anyway, if the address system extended to these suburbs.
Hickory Hills to O'Hare International Airport
The concurrent US 12/20/45, past 87th Street, briefly becomes a 4-lane freeway as it intersects with Illinois Route 171 (Archer Avenue) in Justice and Interstate 55 (the Stevenson Expressway) in Hodgkins (along with Interstate 294, which only has a southbound interchange ramp). North of Interstate 55, US 12/20/45 becomes a regular 4-lane highway before it intersects with the former US 66 at Joliet Road in Countryside.
In Downtown La Grange, US 12/20/45 intersects the Burlington Northern/Santa Fe railroad tracks and intersects with US 34 (Ogden Avenue), possibly the only intersection of 4 separate US routes in Illinois.
Following the intersection with US 34, US 12/20/45 passes through La Grange Park (as La Grange Road), moving in a slight northwesterly direction. After passing over Salt Creek, US 12/20/45 intersects with Cermak Road/22nd Street in Westchester and is known as Mannheim Road north of this intersection. Mannheim Road, as US 12/20/45 serves as the Eastern starting point for Illinois Route 38 (Roosevelt Road) in Hillside, has a full interchange with Interstate 290, also in Hillside, and serves as the Eastern starting point for Illinois Route 56 (briefly Washington Boulevard in Bellwood, before becoming Butterfield Road).
After passing over a Union Pacific rail yard, US 45 becomes concurrent with only US 12 in Melrose Park as US 20 breaks off at Lake Street there. US 12 and US 45 remain concurrent on Mannheim Road, passing Interstate 294 again without an interchange, but, after passing Illinois Route 19 (Irving Park Road), has a full interchange with Interstate 190, which leads directly to O'Hare International Airport or Interstate 90 East (into Chicago). This area between IL19 and IL72 once ran straight though but was realigned to the east in 1960 for the construction of O'Hare's 4R/22L runway.
Near the Northeast portion of O'Hare airport, US 12/45 intersects with Illinois Route 72 in Rosemont, IL, and continues along Mannheim Road into Des Plaines. Mannheim Road ends and feeds into Lee Street at the end of an S-curve. The northbound and southbound routes are split in downtown Des Plaines between Lee Street (West 12/North 45) and Graceland Avenue (East 12/South 45). During this time, US 12/45 intersects with US 14 (Miner Street) at two separate points, due to the separation of their directions.
Just north of US 14, US 12/45 are reunited in both directions on Lee Street, only to be separated as US 12 diverges onto Rand Road and US 45 becomes Des Plaines River Road in a complicated intersection on the north side of Des Plaines, just south of Illinois Route 58.
Initially, US 45 ran from Metropolis to Des Plaines, Illinois, with some portions under construction.[2] In 1929, a ferry that once crossed the Ohio River closed in favor of opening Brookport Bridge.[3] By 1930, most of the sections were finished and then opened to traffic.[4] The original alignment followed (from south–north) what used to be part of IL 1, IL 140, IL 25, IL 44, IL 51, and IL 46 before terminating at US 12.[5] These state routes were eventually either truncated or removed as of 1935.[6] That same year, US 45 was extended north from Des Plaines, Illinois to Michigan.[7][8] In 1936, a new bridge crossing the Des Plaines River, Chicago Sanitary and Ship Canal, and the Illinois and Michigan Canal opened. As a result, US 45 moved off from another bridge carrying Willow Springs Road.[8] In 1940, US 45 was rerouted to branch off west from Half Day instead of branching off north of Libertyville.[9]
In 1954, a portion of US 45 south of Kankakee moved eastward, resulting in the extension of IL 115.[10] In 1962, another portion of US 45 east of O'Hare Field moved slightly eastward.[11] In 1969, a portion of Interstate 57 east of Kankakee was extended south to US 54 west of Onarga. As a result, US 45 moved away from Clifton and Chebanse.[12]
In October 2019, the 4-lane Millburn Bypass opened in order to reduce congestion in and near Millburn.[13]
^ abIllinois Technology Transfer Center (2007). "T2 GIS Data". Retrieved 2007-11-08.
^Illinois Secretary of State; H.M. Gousha (1928). Illinois Official Auto Road Map (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Secretary of State; H.M. Gousha (1929). Illinois Official Auto Road Map (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Secretary of State (1930). Official Illinois Highway Map (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Secretary of State (1931). Official Illinois Highway Map (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Secretary of State; H.M. Gousha (1935). Official Road Map Illinois (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^ abIllinois Secretary of State; Rand McNally (1936). Road Map Illinois (Map). [c. 1:950,000 and c. 1:1,110,000]. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Secretary of State; Rand McNally (1940). Illinois Road Map (Map). c. 1:918,720. Springfield: Illinois Secretary of State. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Division of Highways; H.M. Gousha (1962). Illinois Official Highway Map (Map). [1:790,00]. Springfield: Illinois Division of Highways. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Division of Highways; H.M. Gousha (1962). Illinois Official Highway Map (Map). [1:790,00]. Springfield: Illinois Division of Highways. Retrieved October 25, 2020 – via Illinois Digital Archives.
^Illinois Division of Highways; Rand McNally (1969). Illinois Official Highway Map (Map). [1:772,500]. Springfield: Illinois Division of Highways. Retrieved October 25, 2020 – via Illinois Digital Archives.
US 45 near Brookport
