The Sandhills of Nebraska, the quiet beauty of the state. Covering 19,000 square miles, it is the largest tract of stabilized sand dunes in the Western Hemisphere. Considered an inhospitable desert by early settlers, the Sandhills instead proved to be prime rangeland for raising cattle. The lush grasslands are nourished by the Ogallala Aquifer, one of the largest groundwater sources in the world. The grassy hills rise up to 400 feet and can be as long as 20 miles. While other parts of the world scream beauty, the Sandhills whisper.