Interstate 90 (I-90) runs east–west through the western, central and southern portions of the U.S. state of Wisconsin. About 187 miles (301 km) of I-90 lie in the state.

Interstate 39 (I-39) is a highway in the Midwestern United States. I-39 runs from Normal, Illinois, at I-55 to State Trunk Highway 29 (WIS 29) in the town of Rib Mountain, Wisconsin, which is approximately six miles (9.7 km) south of Wausau. I-39 was designed to replace U.S. Route 51 (US 51), which, in the early 1980s, was one of the busiest two-lane highways in the United States. I-39 was built in the 1980s and 1990s.