Gore's Cave
Boise City-Nampa, ID, Idaho
33.1 miles SE of Boise City-Nampa, ID, IdahoGore's Cave is a remote desert lava tube hidden in the high-desert plains southeast of Boise, Idaho — a hollow volcanic tunnel left behind by molten lava that once flowed across the Snake River Plain. For Boise-area explorers willing to venture off the beaten path, it's a genuine slice of underground adventure: a cool, dark cave carved entirely by ancient volcanic activity, far from the crowds.
Like Idaho's other lava tubes, Gore's Cave formed when a river of molten rock crusted over on the surface while the lava beneath kept flowing and eventually drained away, leaving a tube-shaped cavern in its wake. The result is a rugged, rocky passage to pick your way through — the kind of place that rewards a sense of adventure and a good light.
Getting there is part of the challenge. The cave lies out in the open desert south of Boise, reached by heading south on Pleasant Valley Road and navigating the dirt tracks beyond — a high-clearance vehicle and a reliable map or GPS are strongly recommended, since there's little signage and the desert roads can be rough. Note that the area sits near the Orchard military training range, so watch for posted signs and stay well clear of any restricted or active zones.
Inside, there's more to see than you might expect for a desert lava tube. Explorers describe “lava candles” and other drip formations along the walls and ceiling, along with sparkling crystal formations, and a few tight side rooms worth a crawl if you don't mind squeezing. A curious feature is the strong wind that whips out of the entrance — a sign the cave connects to other openings underground. Note that some visitors have found the main passage partly collapsed or filled in over the years, so conditions can change, and the entrance, while right along the road, can be genuinely hard to spot.
One serious warning: this is prime rattlesnake country. Multiple visitors report seeing lots of rattlesnakes here, especially in the warmer months, so watch carefully where you step and put your hands, both around the entrance and inside the cave.
Come prepared for true backcountry caving. Bring at least two light sources (a headlamp plus a backup), wear a helmet and sturdy closed-toe shoes, and pack a layer, since the cave stays cool even when the desert above is baking. There's no water, no shade, and no cell service out here, so carry plenty of water, tell someone your plans, and never explore a cave alone. Watch your footing on the loose, rocky floor.
For those who like their adventures a little off-grid, Gore's Cave delivers — a quiet, otherworldly lava tube in the wide-open Idaho desert, and a reminder of the volcanic forces that shaped this whole corner of the state. Pack your lights, bring a friend, and leave it just as wild as you found it.