Having heard legends of little spirits living at Paha Wakan, now know as Spirit Mound, the Lewis and Clark expedition was intrigued. On August 25, 1804, while the rest of the expedition went on up the river, Captains Lewis and Clark took several men and Lewis' dog, Seaman, on a nine mile walk to Spirit Mound. Seaman, suffering from the heat, had to be sent back to the Vermillion River. Despite the rumors of danger, the men approached the hill and climbed to the summit. The men were deeply impressed by the view. The hiking trail leads visitors approximately three-quarters of a mile from the parking lot to the summit. Interpretive signs along the trail tell the story of Spirit Mound. According to their journals, we know that Lewis and Clark actually stood on the summit. The area has a rich variety of prairie wildflowers and grasses, such as wild rose hips, evening primrose, sunflowers, silky aster and whorled milkweed. The prairie is home to Fritillary butterflies, birds and many other prairie animals. Over 300 acres of the prairie are currently being restored.