There are a wide variety of trails to ride in Lime Creek. Since the land is discarded quarry property donated by the cement plants it's pretty rocky and not typical of Iowa terrain. The land managers tend to be prejudiced towards cyclists, not sure why. The marked trails range from rocky singletrack to bark and gravel coverd wide trails, if you know where to look you can find some highly technical and challenging singletrack. There's news of a new trail under construction that runs along the Winnebago River, the word on the streets is that it's some of the best singletrack in Iowa, they call it the Soar Trail.
How to get there:
Highway 65 North out of Mason City, take a right into Lime Creek, there will be a sign. You can park where the road turns right and explore or you can follow the road to the Nature Center and explore from there. You can also ride a river trail from 12th Street North in town, it connects with the Nature Center trails, there's a parking area behind the car wash on 12th street.