(Guard Tower #41, 1857, MI-38-31) at Jackson Maximum Facility N. of Jackson, Blackman Township, Jackson County, MI. MI106 (Cooper St.) N. 1.6 miles from jct with I94 exit 139 on the N. side of Jackson to the turret on the E. side of the road. Tower #41 is at the NE corner of the facility & near the hospital. (N42 17.888 W84 23.301) Photo by Mark Comstock 6-5-22.