Fodor's Expert Review Ruby Falls
More than 80 years ago, Leo Lambert and a small crew spent 17 hours inside this cavern before discovering what is now the world's tallest and deepest underground waterfall (145 feet) open to the public. Guided tours begin every few minutes. After your visit underground, head up the 70-foot-high Lookout Mountain tower for a spectacular panorama of the Tennessee River Valley, either with your own peepers or by using one of the coin-operated telescopes. Younger children can romp on the Fun Forest Playground or pan for gems. For an adult adrenaline rush, the ZIPstream experience is a suspended obstacle course, culminating in 700 feet of round-trip zip-lining with fabulous views of Chattanooga. The temperature inside the cave is 60°F, so bring a light sweater or jacket.