"Cumberland Caverns is the largest show cave and second-longest cavern in Tennessee. Designated a National Historical Landmark, it was once home to mines for saltpeter, which was used to make gunpowder during the War of 1812 and the Civil War. The site has been a popular attraction since the 19th century and now offers year-round daily tours, including easy walks, more-strenuous caving adventures, and even overnight excursions that visit difficult-to-navigate sections of the caves. Whichever you choose, you’ll be rewarded with views of the Hall of the Mountain King—a massive chamber that serves as one of the largest cave rooms in North America—as well as towering stalagmites, dangling stalactites, and delicate limestone and gypsum formations known as curtains and flowers. The caverns also host live musical performances by major tour acts, taking advantage of the unique acoustics within the caves."