The Dells of the Wisconsin River is a five-mile sandstone gorge in south-central Wisconsin, shaped about 15,000 years ago when meltwater from Glacial Lake Wisconsin burst through after an ice dam failed. Part of the Driftless Area, the gorge escaped direct glaciation and developed dramatic cliffs, side canyons, and distinctive rock forms. Its varied rock faces and surrounding oak and pine habitats support rare plants, animals, and birds, leading to protection of sensitive areas. People have known and used the gorge for thousands of years, from Paleo-Indian times through Ho-Chunk, Sac, and Menominee history. It later became famous through H. H. Bennett’s 1886 photograph and was altered by the 1909 Kilbourn Dam.