High Quality Content by WIKIPEDIA articles! M-28 Business Route (BUS M-28) is a state trunkline highway serving as a business route that runs for 4.841 miles (7.791 km) through the downtown districts of Ishpeming and Negaunee in Michigan. The trunkline provides a marked route for traffic diverting from U.S. Highway 41 (US 41) and M-28 through the two historic iron-mining communities. It is one of three business loops for M-numbered highways in the state of Michigan. There have previously been two other BUS M-28 designations for routes in Newberry and Marquette.