The Potawatomi Trail, in Pinckney State Recreation Area, is a 17.5 trail which is scenic, somewhat hilly and somewhat technical. It is open to mountain biking as well as hikers. Mountain bikers are encouraged to travel clockwise while hikers, counter clockwise. The trail does has several sub-routes where you can traverse shorter distances however the full trail is 17.5 miles.
The Potawatomi Trail has a Strava Segment (but the trail name is mis-spelled).