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 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.
Route description
Only one segment of US 12 is included in the NHS. That is the segment that is concurrent with US 20 from the Illinois state line to the split with US 20 in East Chicago. The NHS is a network of highways that are identified as being most important for the economy, mobility, and defense of the nation. The highway is maintained by INDOT like all other U.S. Highways in the state. The department tracks the traffic volumes along all state highways as a part of its maintenance responsibilities using a metric called annual average daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that the lowest traffic levels were 3,120 vehicles and 350 commercial vehicles used the highway daily near Ogden Dunes. The peak traffic volumes were 30,510 vehicles and 2,430 commercial vehicles AADT along the section of US 12 at the Illinois state line, concurrent with US 20 and US 41. The highway has been designated as the Iron Brigade Memorial Highway to honor the Civil War Union Army unit; it has the same designation in Michigan, Wisconsin, and Illinois.
Whiting to Gary
US 12 enters Indiana concurrent with US 20 and US 41, at which point it passes under the Indiana Toll Road. The road passes both commercial and industrial areas between Wolf Lake and Horseshoe Hammond. US 12, US 20, and US 41 are concurrent until US 41 turns south on Calumet Avenue. Both US 12 and US 20 head southeast toward East Chicago, where US 12 turns east while US 20 continues south. The route heads east through East Chicago as a four-lane undivided highway passing through mostly residential areas. The road heads south concurrent with SR 912, passing through mainly industrial area between East Chicago and Gary. The two routes have an interchange at SR 312 and access to the Indiana Toll Road, via an interchange at Gary Avenue. The road has two bridges with the first passes over the Grand Calumet River and the other passing over the Indiana Toll Road and the South Shore Line.