Tongue River Cave is one of Wyoming's most notable wild caves — a genuine, undeveloped cave in the Bighorn National Forest just west of Dayton, near the mouth of scenic Tongue River Canyon. With roughly 6,500 feet of surveyed passages winding through canyons, stream channels, and named rooms like the Rain Room and Wind Tunnel, it's a real adventure for prepared, experienced cavers.

This is no tourist show cave: it's a rugged, muddy, technical wild cave that demands proper gear, multiple light sources, a helmet, warm layers, and real experience navigating undeveloped passages (ideally a trip with people who know the cave). The gated entrance opens to a small room with a pit, and the system requires care throughout.

Important access rules — this cave is gated and managed for protection. The Forest Service has installed a bat-friendly gate, and you must register with the U.S. Forest Service and obtain a permit before entering. The cave is also closed every year from October 15 through April 15 to protect hibernating bats — please honor that closure. Decades of heavy traffic and vandalism have sadly stripped the cave of many of its formations, so tread lightly and take nothing; every visitor helps determine what's left for the future.

The drive to the Tongue River Canyon trailhead is gorgeous, and the canyon itself offers great hiking and climbing if the cave isn't your aim. If you do go underground, go prepared, get your permit, never cave alone, tell someone your plans, and follow strict cave-conservation and white-nose-syndrome decontamination practices. For experienced cavers, Tongue River Cave is a classic Bighorn underground adventure.