My fiancée and I were able to take some time off from work and school in May so we can visit my family in Indiana. We will be taking our new 4Runner and our two dogs along on the trip. Depending on weather, traffic, etc... we plan to take Interstate 90 East to Sioux Falls, SD. Then either continue on 90 through southern Minnesota or south on interstate 29 into Iowa then onto Interstate 80 East. Does anyone in Iowa or Minnesota know of any good spots to stretch out and let our dogs roam for awhile along either of these routes? Any info would be great! Not looking to hit any trails and the closer to the route the better since we will be on a schedule.