Ruby Falls is a stunning underground waterfall located within Lookout Mountain in Chattanooga, Tennessee. It is one of the tallest underground waterfalls in the United States, cascading 145 feet into a cavern. The falls were discovered in 1928 by Leo Lambert during a cave exploration. Visitors can access Ruby Falls through guided tours that take them through the Ruby Falls Cave. The tour includes a scenic walk through the cave's formations, leading to the breathtaking view of the waterfall. The site is a popular attraction, drawing nature lovers and adventure seekers alike.