Stock photography, photos: Waterfall Over a Tufa Formation Stock photos of Waterall over a Tufa Formation on Trimble Creek in the Lower Howard's Creek Nature and Heritage Preservelocated in the Bluegrass Region of Kentucky, USA.  Photograph: © Jim Lane Click for a larger image and more information Keywords associated with this stock photo: America, color, colour, creek, Kentucky, KY, nature, park, peaceful, preserve, serene, stream, tranquil, tufa, United States, USA, vertical, waterfall