Michigan State Route 13 is a north-south highway South-Central and Northeastern Bay County. It runs from the Bay/Saginaw County Line, near Bay City, to the Bay/Arenac County Line, near Worth. MI St Rt 13 passes through the following towns in Bay County. Bay City
Branches of MI St Rt 13 in Bay County. A guide sign on NB MI St Rt 84. A junction marker on EB BUSN Spur I-75/MI St Rt 25. NB MI St Rt 13 north of Wilder Road. NB MI St Rt 13 south of MI St Rt 247. A guide marker on SB MI St Rt 247.