Michigan Highway 55 is one of the east-west routes spanning the width of the Lower Peninsula, upstate of the landmass's center. Michigan Highway 55 is positioned such that about a third of the Peninsula's total north-south height lies north of the highway. That means it rides along what we might consider the boundary between central and northern Michigan. The western end is at US Route 31 in Manistee. Michigan Highway 55 begins there and heads east along a fairly straight path. It passes through Cadillac, Lake City, Houghton Lake, and West Branch. At Tawas City, along the Lake Huron shoreline where Saginaw Bay empties into the rest of the lake, Michigan Highway 55 ends at US Route 23.
My photo of Michigan Highway 55 comes from West Branch, Michigan, where the state route crosses Interstate 75. The signage depicted is a pair of eastbound reassurance markers for traffic heading away from the Interstate 75 interchange. Interstate 75 spawns a business loop here that follows Michigan Highway 55 into West Branch, so that business loop is mentioned here, too. This photo was taken in March 2019 as I was driving around central and southern Michigan.