The closest listing to Detroit is Addison Oaks County Park, about 36 mi away. 3 places to camp sit within 50 miles, 8 within 100, and 26 within 150. Every one carries weather, wildfire proximity and a straight link to the official booking site, and the federal ones show live availability.
Federal campgrounds where the app shows how many sites are open tonight.
A lake, river or beach you can get into from camp.
No published nightly fee. Permits and day-use charges can still apply.
The listing says pets are welcome. Leash rules are on each one.
An agency document names accessible sites. The source is on each listing.
Distances are straight-line miles from Detroit, not drive times. Mountain roads can double them.