18 of America's great show caves and underground wonders.
Beneath America's surface lies a world of limestone cathedrals, glittering formations, and lava tubes. This is a curated checklist of 18 of the best caves and caverns you can tour, grouped by type, with each one's location and what it's known for — a planner for anyone drawn to the underground.
| Cave | Location | Known For |
|---|---|---|
| Mammoth Cave National Park | Mammoth Cave, KY | Longest in world · 426+ mi surveyed |
| Carlsbad Caverns National Park | Carlsbad, NM | Big Room is largest cave chamber in U.S. |
| Wind Cave National Park | Hot Springs, SD | Box-work formations |
| Jewel Cave National Monument | Custer, SD | 3rd-longest in world |
| Oregon Caves National Monument | Cave Junction, OR | Marble interior |
| Lava Beds National Monument | Tulelake, CA | Lava tube caves |
| Cave | Location | Known For |
|---|---|---|
| Luray Caverns | Luray, VA | Stalacpipe Organ |
| Howe Caverns | Howes Cave, NY | subterranean lake boat ride |
| Ruby Falls (Lookout Mountain) | Chattanooga, TN | 145 ft underground waterfall |
| Meramec Caverns | Sullivan, MO | 7-story formations |
| Cumberland Caverns | McMinnville, TN | Volcano Room concerts |
| Cave | Location | Known For |
|---|---|---|
| Marengo Cave | Marengo, IN | National Natural Landmark |
| Kartchner Caverns State Park | Benson, AZ | most-pristine recent discovery |
| Bluespring Caverns | Bedford, IN | underground river boat tour |
| Sea Lion Caves | Florence, OR | only sea-cave with sea lion colony |
| Cave | Location | Known For |
|---|---|---|
| Ape Cave (Mt. St. Helens NM) | Cougar, WA | Longest lava tube in continental U.S. |
| Volcanoes National Park (Nahuku Lava Tube) | Volcanoes NP, HI | Walk-through lava tube |
| Lava River Cave | Bend, OR | 1 mi long |
Turn this list into a keepsake. The Triptyka Caves & Caverns Passport is a printable PDF with a curated checklist, a detail page for each cave, suggested routes, and achievement badges to earn.
Get the Printable Passport — $9.99 on Etsy →Bring a jacket; most caves stay around 50–55°F year-round regardless of the weather outside. Book tours ahead, especially at national-park caves like Carlsbad and Mammoth, where popular tours sell out. Never touch the formations — oils from your hands stop them growing. Follow bat-protection rules; many caves ask visitors to walk through decontamination mats to help slow white-nose syndrome, a disease devastating North American bats.
Mammoth Cave in Kentucky is the longest known cave system on Earth, with more than 400 miles surveyed and more still being mapped.
Wear a light jacket and closed, non-slip shoes. Most show caves stay cool — around 50–55°F — all year, and paths can be damp and uneven.
For popular national-park caves like Carlsbad Caverns and Mammoth Cave, yes — guided tours often sell out, especially in summer. Many commercial show caves accept walk-ups.
Oils and dirt from your hands can permanently stop a formation from growing and discolor it. Stalactites and stalagmites grow incredibly slowly, so touching causes lasting damage.
A printable caves and caverns passport — a curated checklist, a detail page for each cave, suggested routes, and achievement badges — makes it easy to mark off each one.