U.S. Route 33 (US 33) is a United States Numbered Highway that runs northwest–southeast for 709 miles (1,141 km) from northern Indiana to Richmond, Virginia, passing through Ohio and West Virginia en route. Although most odd-numbered U.S. routes are north–south, US 33 is labeled east–west throughout its route, except in Indiana where it is labeled north–south. It roughly follows a historic trail used by Native Americans from Chesapeake Bay to Lake Michigan.

U.S. Route 24 or U.S. Highway 24 (US 24) is one of the original United States Numbered Highways of 1926. It originally ran from Pontiac, Michigan, in the east to Kansas City, Missouri, in the west. Today, the highway's eastern terminus is in Independence Township, Michigan, at an intersection with Interstate 75 (I-75), and its western terminus is near Minturn, Colorado, at an intersection with I-70. The highway transitions from north–south to east–west signage at the Ohio–Michigan state line.