The Wilderness Act of 1964 recognized wilderness as an area where the earth and its community of life are untrammeled by man, and where man is a visitor who does not remain. At Dinosaur National Monument, the Green and Yampa rivers flow for 107 miles through remote canyons seen by only a few thousand people each year. Its 211,000 acres include stark beauty, quiet reflection, and whitewater rapids, with solitude readily available, natural sounds prevailing, and stars unmarred by city lights. In 1978, the National Park Service recommended over 200,000 acres of Dinosaur National Monument for wilderness designation. While Congress has not made a final determination, this rugged landscape continues to be managed to preserve its wilderness character, and today over 90% of the monument remains undeveloped without permanent structures or roads.