Incredible US Caves and Caverns

Go 211 feet underground to see the deepest part of the largest caverns in Texas. Natural Bridge Caverns — located near New Braunfels, Texas — continues to be an active and growing cavern system, with water flows causing the underground formations to retain their waxy luster. Visitors can take several different types of guided tours, including the Bracken Bat Flight Tour for an up-close view of the Bracken Cave, home to the world’s largest bat colony.

While camping in Missouri's Ozark Mountains, we recommend a trip to Meramec Caverns to see how an ancient limestone "Wine Table" and an entire seven-story mansion were built underground. In addition to these unique attractions, pre-Columbian Native American artifacts have also been found in the caverns, formed from the erosion of large limestone deposits millions of years ago. Every year, more than 150,000 visitors walk through the 4.6-mile cavern system.

Halfway between Big Bend National Park and San Antonio, Texas, the Caverns of Sonora is one of the most active caves in the world, with more than 95 percent of its formations still growing. Outdoor enthusiasts can camp in a tent or RV nearby. You can’t leave this natural landmark without tasting fresh cream and butter fudge made at the caverns.

Located in Vallecito, California, Moaning Cavern received its mysterious name from what some believe to be a moaning sound from the cave that lured gold miners to the entrance in the 1850s. Today, visitors can take a walking tour or rappel down a 165-foot-tall vertical shaft located in the cavern’s main chamber. Moaning Cavern is home to some of the oldest human remains discovered in America; it is the final resting place for the bodies of prehistoric people who fell into its opening.