Michigan State Route 66 is a north-south highway in Eastern Osceola County. It runs from the Osceola/Mecosta County Line, north of Barryton, to the Osceola/Missaukee County Line, near McBain. MI St Rt 66 passes through the following town in Osceola County. Marion MI St Rt 66 is not multi-plexed in Osceola County. MI St Rt 66 intersects the following highways in Osceola County. U.S. Rt. 10, near Sears.
