Mackinac Island is a beautiful place and no motor vehicles are allowed there. It is only open during the summer months and you ride a ferry over and back.
When you get there you either walk, ride by horse and carriage, or bicycle.
When I drove the big truck out of Chicago, they sent me to Milwaukee to pick up a load that delivered 6 miles south of the Straits of Mackinac. So I went north. It was the shortest way to the drop. I still remember driving across the Mackinac bridge at daybreak and seeing the islands in the Strait. It was beautiful.