Near Shoepac Lake State Forest Campground in Michigan. There are 5 sinkholes in a row, with a 2-mile hike around them. If you choose to go down 209 steps - and then back up, of course - you can visit the bottom of this one. We survived the climb.
Ha ha! https://www.michigantrailmaps.com/member-detail/sinkholes-pathway/
