US Highway 12 (US 12) is a US Highway that runs from Aberdeen, Washington, to Detroit, Michigan. In Michigan it runs for between New Buffalo and Detroit as a state trunkline highway and Pure Michigan Byway. On its western end, the highway is mostly a two-lane road that runs through the southern tier of counties roughly parallel to the Indiana state line. It forms part of the Niles Bypass, a four-lane expressway south of Niles in the southwestern part of the state, and it runs concurrently with the Interstate 94 (I-94) freeway around the south side of Ypsilanti in the southeastern. In between Coldwater and the Ann Arbor area, the highway angles northeasterly and passes the Michigan International Speedway. East of Ypsilanti, US 12 follows a divided highway routing on Michigan Avenue into Detroit, where it terminates at an intersection with Cass Avenue.