My Mom & I biked the Linn Creek Trail in Marshalltown this weekend. The 8-mile trail winds through Marshalltown and ends at Grimes Farms nature center to the west and Riverside Park to the east.
We ended up biking the whole trail and back, over 17 miles, because we were having so much fun exploring. The stretch of trail between 6th Street (by the YMCA) and Grimes Farm was the prettiest. We rode past prairie flowers and softball fields. You can find a map of the trail on the Marshalltown website: https://ci.marshalltown.ia.us/static/departments/parks/bike_trail_info.php