Fall in Illinois brings cool air, colorful leaves, and perfect hiking weather. If you are trying to get out more and enjoy this season, then it's time to check out small towns in Illinois. About Leon D. Larson Memorial ParkWhile this spot is well known by locals, many people in Illinois don't know what they are missing. According to OIYS this is a Fall spot everyone needs to see. Many have stated that this trail is one of their favorite spots to travel along.