Route: Elroy-Sparta State Trail (WI)

https://dnr.wisconsin.gov/topic/parks/elroysparta

The Elroy Sparta trail is a beautiful trail through central Wisconsin.  It is a mostly crushed limestone multi-use trail that is popular for bikes.  It is a former train route that has long train tunnels where bikers & runners need headlamps.  

From the Wisconsin state park website: Considered the first rail-to-trail in the United States, the Elroy-Sparta State Trail remains one of the most popular trails in the country. With three rock tunnels and five small towns along its 32.5-mile route, the trail is a favorite Wisconsin bicycling destination. Traveling between Sparta and Elroy, the trail stretches through the communities of Norwalk, Wilton and Kendall, passing by wetlands, prairies, farmland and unglaciated areas.

Note that the trail is open from 6:00am to 11:00pm.  Please respect all regulations.