^Looking north from the Wisconsin border, December 2017.
Michigan Highway 189 is a short route in the southwestern Upper Peninsula, running from Iron River south to the Wisconsin border. This description is similar to one that would fit Michigan Highway 73, which also begins in Iron River. However, Michigan Highway 73 runs southwesterly from a point in Iron River farther west along US Route 2. Unlike the angled path of Michigan Highway 73, Michigan Highway 189's course is straight south from US Route 2. That northern terminus at US Route 2 is in the heart of downtown Iron River. The southern terminus is at the state line, whereupon Michigan Highway 189 becomes Wisconsin Highway 139. Michigan Highway 73 reaches the state line farther west, which becomes Wisconsin Highway 55, bound for towns like Crandon. Wisconsin Highway 139, which takes over for Michigan Highway 189, runs southerly toward the Wisconsin places of Laona and Wabeno.
My photo of Michigan Highway 189 comes from its southern terminus, at the Wisconsin state line. The signage depicted is the first reassurance marker shown to northbound travelers who just crossed the border out of Wisconsin. This photo was taken in early December, 2017, as part of an impromptu trip mainly to northern Wisconsin; this weekend trip commenced because of unusually favorable weather, and included several slight forays into Upper Michigan.