Ape Cave
A lava tube near Mount St. Helens with two self-guided routes: an easy lower section and a rougher upper one with an 8-foot rock wall to climb. Bring two light sources each.
Cougar, WA, 42°F inside
Lava tubes you can walk through
A lava tube is a tunnel left behind when the outside of a lava flow cooled and the molten rock inside drained away. Most are run by the Forest Service or the Park Service, have no guides and no lights, and stay cold all year. Bring two light sources each, warm layers and sturdy shoes.
6 caves. Each note is taken from the cave's own site or park page; the date we checked is on each cave's page. Rules change, so confirm before you go.
Explore on your own
No guide and no lighting. Some need a timed reservation or a free permit.
Lava River Cave
A mile-long lava tube north of Flagstaff that you explore on your own. Bring two or three lights, warm clothes and sturdy shoes.
Flagstaff, AZ, 35–45°F inside
Subway Cave
A lava tube in Lassen National Forest with a self-guided trail about a third of a mile long. It's completely dark, so bring a flashlight.
Old Station, CA, 46°F inside
Craters of the Moon Caves (Indian Tunnel)
Lava tubes reached by a 1.6-mile round-trip trail in Craters of the Moon National Monument. Indian Tunnel is the easiest, an 800-foot tube lit by natural skylights; Dewdrop Cave is harder.
Arco, ID
Kaumana Caves
A skylight into a long lava tube on the edge of Hilo. A very steep stairway leads down into two openings; bring a flashlight to go further in.
Hilo, HI
Lit trails and short walks
Thurston Lava Tube
Nāhuku, a lava tube in Hawaiʻi Volcanoes National Park you walk through on your own; it's lit from 8am to 8pm and covered by the park entrance fee.
Hawaii