U.S. Route 45 (US 45) is a major north-south United States highway and a border-to-border route, from Lake Superior to the Gulf of Mexico. A sign at the highway's northern terminus notes the total distance as 1,297 miles (2,087 km).

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 serves as the western boundary of the University of Illinois at Urbana–Champaign campus.

State Route 45 (SR 45) is a state highway in the U.S. State of California that travels in a north–south direction in the Sacramento Valley from Route 113 in Knights Landing to Route 32 in Hamilton City.

State Road 45 forms a 300 mile long highway between Naples and High Springs along western reaches of the Florida peninsula. The route is vastly unsigned as the companion of U.S. 41 through Fort Myers, North Port, Sarasota, Bradenton, Brooksville and Williston.

U.S. Route 45 is a major North-South route of the U.S. Highway system with U.S. Route 45W and U.S. Route 45E, stretching just over 1,297 miles (2,087 km) from Pascagoula, Mississippi to Ontonagon, Michigan.

US 45 begins in Michigan on the shores of Lake Superior. It heads south through Wisconsin, arriving in Oshkosh and then Milwaukee before continuing south through Chicago's western suburbs. From there it runs the length of Illinois crossing the Ohio River into Paducah, Kentucky.

The I-45 Interstate 45 Highway is a major traffic corridor and interstate highway that travels generally in a north-south direction across the eastern portion of Texas state.

State Road 45 from south of Bay Dr to south of 63rd Ave W is an urban highway with a 6-lane undivided roadway located south of Bradenton in Manatee County. The existing facility has a two-way left-turn lane and sidewalks on both sides.

2023年12月16日 · US 45 ended at Northwest Highway, which at the time carried US 12 traffic. This photo shows the scene: That was looking north on Lee at Northwest Hwy (which is now US 14). Here we are looking the opposite direction (south on Lee from Northwest Hwy) at an historic north beginning of US 45:

Indiana State Road 45 is a two lane highway that runs north/south through Bloomington. It originally extended from the southern border of Indiana down near Rockport and Evansville and goes until it reaches its end at SR 135 north east of Bloomington. Its southern terminus is now at US 231 near NSA Crane.