The "400" Trail
Biking the "400"
I've ridden every Rails-to-Trails trail in the southern half of Wisconsin, and my favorite is the "400" Trail. It runs from Reedsburg to to Elroy, about 42 miles round trip on the railbed of the old Chicago Northwestern. The "400" was an express train from Chicago to Minneapolis that proudly made the 400-mile run in 400 minutes behind a pair of big 4-6-2 steam locomotives.
The main trailhead is at the old depot in Reedsburg, at the southeast end of the trail. In my opinion, the most beautiful segment of the trail is between La Valle and Wonewoc. My heart races a bit just to think about that ride. The least interesting segment is north/west of Wonewoc, especially the last few miles into Elroy. But of course in Elroy you arrive at Elroy Commons, trailhead for the "400", the Elroy-Sparta and the Omaha trails: a real bicycling crossroads. It's worth the trip.
Kayaking the Baraboo
A lot of the trail runs along the winding Baraboo River, which you can also kayak from Union Center down to Wonewoc. You rent your kayak at Beyond Boundaries in Wonewoc, and they'll ferry you up to Union Center to put in and come back down through woods and fields back to the landing at Wonewoc.