U.S. Route 54 is an east–west United States Highway that runs northeast–southwest for 1,197 miles (1,926 km) from El Paso, Texas, to Griggsville, Illinois. The Union Pacific Railroad's Tucumcari Line runs parallel to US 54 from El Paso to Pratt, Kansas, which comprises about two-thirds of the route.
Illinois Route 19 is a major east–west arterial state highway in northeastern Illinois, United States. It runs from Illinois Route 25 in Elgin, to Lake Shore Drive on the north side of Chicago. Illinois 19 is 33.64 miles (54.14 km) long. For much of its length, it is also known as Irving Park Road and Chicago-Elgin Road.
Illinois Route 71 is a 66-mile-long (106 km) southwest-to-northeast state highway in north central Illinois. It runs from the end of Interstate 180 in Hennepin to U.S. Route 34 in Oswego. This is a distance of 69.37 miles (111.64 km).
Illinois Route 43 is a 60.30-mile-long (97.04 km) major north–south state highway in the U.S. state of Illinois. It runs from U.S. Route 30 (US 30) in Frankfort north to the large intersection of IL 120 and US 41 in Waukegan.
Illinois Route 171 (IL 171) is a 38.61-mile-long (62.14 km) north–south state highway in northeastern Illinois. It runs from U.S. Route 6 (US 6) in Joliet north to Illinois Route 72 at the Chicago–Park Ridge border. The section of IL 171 on Archer Avenue from Joliet to Summit is historically significant, originating as a Native American trail, and later serving for a time as part of the first numbered highway between St. Louis and Chicago.
Illinois Route 2 is a north–south state highway in northern Illinois. It currently starts at Illinois Route 40 in Sterling and ends at the Wisconsin state line in South Beloit, very near the intersection with U.S. Route 51, Illinois Route 75 and Illinois Route 251. Illinois 2 is 73.91 miles (118.95 km) long.
Illinois Route 4 is a major north–south highway that runs south from the Interstate 55 business loop around the state capital of Springfield, south to Illinois Route 13 just north of Murphysboro. This is a distance of 170.44 miles (274.30 km).
Lake Street is an east–west street in Chicago and part of its suburbs. A portion of Lake Street is designated as U.S. Route 20. Lake Street begins in downtown Chicago and travels west to the eastern terminus of the Elgin Bypass around suburban Elgin. The street travels west through the city and then begins to travel in a northwest fashion through several suburbs. The street is a distance of roughly 34.4 miles (55.4 km).
Illinois Route 91 (IL 91) is a rural state route in central Illinois. It runs from the northwest edge of Peoria at U.S. Highway 150 (US 150) to U.S. Highway 34 and Illinois Route 78 south of Kewanee. Illinois 91 is 40.72 miles (65.53 km) long.
Illinois Route 18 is a rural east–west state route in central Illinois. It runs east from the town of Henry at Illinois Route 29 to the town of Blackstone at Illinois Route 17. This is a distance of 39.01 miles (62.78 km).
U.S. Route 6 (US 6) in the state of Illinois is an east–west arterial surface road that runs 179.88 miles (289.49 km) from the city of Moline in the Quad Cities area to Lansing at the Indiana state line.
U.S. Route 12 (US 12) in the U.S. state of Illinois is an arterial highway that runs northwest to southeast through the Chicago metropolitan area. It enters Illinois at the Wisconsin border north of Richmond, and exits into Hammond, Indiana, from Chicago near the foot of the onramp to the Indiana Toll Road ; as it exits Illinois, the route is also concurrent with US 20 and US 41. Within Illinois, US 12 runs for a distance of 85.14 miles (137.02 km).
Sheridan Road is a major north-south street that leads from Diversey Parkway in Chicago, Illinois, north to the Illinois-Wisconsin border and beyond to Racine. Throughout most of its run, it is the easternmost north-south through street, closest to Lake Michigan. From Chicago, it passes through Chicago's wealthy lakeside North Shore suburbs, and then Waukegan and Zion, until it reaches the Illinois-Wisconsin state line in Winthrop Harbor. In Wisconsin, the road leads north through Pleasant Prairie and Kenosha, until it ends on the south side of Racine, in Mount Pleasant.
U.S. Route 41 (US 41) in the U.S. state of Illinois runs north from the Indiana border beneath the Chicago Skyway on Indianapolis Boulevard to the Wisconsin border north of the northern terminus of the Tri-State Tollway with Interstate 94. It is the only north–south U.S. Route to travel through a significant portion of the city of Chicago, carrying Lake Shore Drive through the central portion of the city along the lakefront. US 41 in Illinois is 64.81 miles (104.30 km) in length.
U.S. Route 54 (US 54) in Illinois is a 23.9-mile-long (38.5 km) east–west highway that travels from the Champ Clark Bridge on the Missouri state line to I-72/US 36/IL 107 south of Griggsville. At its greatest extent, US 54 used to continue east to Springfield, then northeast to Onarga, and then north all the way to Downtown Chicago.
U.S. Route 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). US 45 is the longest numbered route in Illinois.
U.S. Route 14 (US 14) in the state of Illinois is a major arterial that runs southeast from the Wisconsin state line north of Harvard to the north side of Chicago at US 41.
The Chicago and Joliet Electric Railway, or C&JE, was an electric interurban railway linking the cities of Chicago and Joliet, Illinois. It was the only interurban between those cities and provided a link between the streetcar network of Chicago and the cities along the Des Plaines River Valley in north central Illinois, which were served by the Illinois Valley Division of the Illinois Traction System.
Several special routes of U.S. Route 40 exist. In order from west to east they are as follows.
Illinois Route 65 was an east–west state highway in the Chicago metropolitan area. It traveled from U.S. Route 30 Business in Aurora to US 34 north of Naperville.
IL 83 / IL 171 
