I fly to Mackinac Island all the time.

The landing fee is $10.

You land at the top of the island; it's a nice 1/2 hour downhill walk
to the town. You will walk through forest and see horses (and horse
poo) and bicycles. It's not hot (the forest keeps things things cool).

The town is fun, small, pretty, and has a great marina. Read the
island website to learn more. I recomend the horse drawn carriage
tour. The tour guides give a nice talk and the tour shows almost
everything except the inside of the fort.

The walk back to the airport is 1/2 hour uphill, or the horse-drawn
taxi is cheap. I always walk.

Fuel can be had at St. Ignace (right across the channel, cheap, nice).

The bridge is close and amazing.

All in all, a nice flight. And you will often see some amazing planes
parked on the island.