I went trail running at Chuck T Crume Nature Park today. The trails are excellent for trail running or walking. The lack of distance makes them short for Mountain Biking, but I've seen bikers on the trails. The park is a great place for city dwellers to take their dog or children. There are leash laws however (for the dogs).
If you run the outer loop of the trail the trail is approximately .75 miles long. There are several inner loops and connecters however, which can be connected to make much longer walks/runs. I ususally run the outer loop several times to make long run of it. If you don't have much time and you are in Bowling Green, seek out this park and take advantage of the trees and trails. You will definately see squirrels, birds, and rabbits, and you might just forget you're in the middle of the city.