Beloit is a city in Rock County, Wisconsin, United States. As of the 2020 census, the city had a population of 36,657 people. Beloit is a principal city of the Janesville-Beloit Metropolitan Statistical Area and is included in the Madison Combined Statistical Area.

Interstate 43 (I-43) is a 191.55-mile-long (308.27 km) Interstate Highway located entirely within the US state of Wisconsin, connecting I-39/I-90 in Beloit with Milwaukee and I-41, U.S. Highway 41 (US 41) and US 141 in Green Bay. State Trunk Highway 32 (WIS 32) runs concurrently with I-43 in two sections and I-94, I-894, US 10, US 41, US 45, and WIS 57 overlap I-43 once each. There are no auxiliary or business routes connected to I-43, though an alternate route to direct traffic during road closures is signed along local and state highways from Milwaukee County north into Brown County.