U.S. Route 12 in Indiana

U.S. Route 12
Iron Brigade Memorial Highway[1]
US 12 highlighted in red
Route information
Maintained by INDOT
Length	46.258 mi[2] (74.445 km)
Existed	November 11, 1926[3]–present
Tourist routes	Lake Michigan Circle Tour
Major junctions
West end	US 12 / US 20 / US 41 in Whiting at the Illinois state line
Major intersections	I-65 in Gary I-90 / Indiana Toll Road in Gary
East end	US 12 in Michiana Shores at the Michigan state line
Location
Country	United States
State	Indiana
Counties	Lake, Porter, LaPorte
Highway system
United States Numbered Highway System List Special Divided Indiana State Highway System Interstate US State Scenic
← SR 11 → SR 13

U.S. Route 12 (US 12) is a part of the United States Numbered Highway System that runs from Aberdeen, Washington, to Detroit, Michigan. In the U.S. state of Indiana, it is part of the state road system. US 12 enters the state concurrent with US 20 and US 41 in Whiting. The 46.258 miles (74.445 km) of US 12 that lie within Indiana serve as a major conduit. Some of the highway is listed on the National Highway System (NHS). Various sections are rural two-lane highway, urbanized four-lane undivided highway, and one-way streets. The easternmost community along the highway is Michiana Shores at the Michigan state line.

US 12 passes through urban areas and wood lands, parallel to the Lake Michigan shoreline. The highway is included in the Lake Michigan Circle Tour and passes through Indiana Dunes National Park. Historical landmarks along the highway include the Miller Town Hall, Beverly Shores station, and the Old Michigan City Light. A memorial highway designations have been applied to the route since 1917, named for the Civil War Union Army unit.

US 12 was first designated as a U.S. Highway in 1926, concurrent with US 20 west of Michigan City. A section of the highway originally served as part of the Dunes Highway, a connection between Gary and Michigan. US 12 replaced the original State Road 43 (SR 43) designation of the highway which dated back to the formation of the Indiana state road system. SR 43 ran from the Illinois state line through Gary to Michigan City and ended at the Michigan state line. In the early 1920s, it was the most important route between Chicago and Detroit and in 1922 the first sections started being paved. The Indiana State Highway Commission, later renamed Indiana Department of Transportation (INDOT), removed US 20 from the section east of Gary in the early 1930s. Most of the route has since been supplanted by Interstate 94 (I-94) and the Indiana Toll Road.