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. Truckers refer to this road as "The Bee Line."
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. From its' western terminus to Schaumburg Road in Elgin, it's known as Chicago Road before becoming Irving Park Road until its' eastern terminus.
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 56 is a 32.52-mile-long (52.34 km) east–west state highway in northern and northeastern Illinois. It runs from the interchange of Illinois Route 47 at U.S. Route 30 in Sugar Grove east to US 12/US 20/US 45 by Bellwood. It is one of only three state highways that require tolls.
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).
Illinois Route 126 (IL 126) is a 17.25-mile-long (27.76 km) east–west state highway in the northern part of the U.S. state of Illinois. It travels from IL 47 in Yorkville to Interstate 55 (I-55) between Plainfield and Bolingbrook.
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).
Illinois Route 35 is a 2.42-mile-long (3.89 km) connector road between U.S. Route 20 in East Dubuque and Highway 35 at the Wisconsin state line. It is currently the shortest state highway in Illinois, a stark contrast to the highway north of the state line, which is Wisconsin's longest highway.
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.
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.
Illinois Route 63 (IL 63) was an east–west state highway in the Chicago metropolitan area. At its latest routing, it traveled from Illinois Route 72 (IL 72) in East Dundee to US 41 in Gurnee.
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.
Illinois Route 118 (IL 118) was an east–west state highway in Illinois. Located in the Chicago metropolitan area, the route traveled from Elmhurst to Maywood primarily along St. Charles Road.
IL 83 / IL 171 
