More than 850 feet long and as tall as a 10-story building, Natural Tunnel was naturally carved through a limestone ridge over thousands of years. William Jennings Bryan called it the "Eighth Wonder of the World." Other scenic features include a wide chasm between steep stone walls surrounded by several pinnacles, or "chimneys." Facilities include two campgrounds, cabins, picnic areas, an amphitheater, a visitor center, a camp store and a gift shop. You'll also find the Wilderness Road historic area, a swimming pool with a 100-foot slide and a chairlift to the tunnel floor. Guests enjoy cave tours and canoe trips on the Clinch River, as well as the Cove Ridge Center, which offers environmental education, conference facilities and overnight dorm accommodations. A camp store and kayak programs are new this year.