Civil Defense Caves

Useful Information

Location: Highway 20 Rexburg interchange, Salem highway 27 km north, from St Anthony Sand Dunes towards Kilgore. At sign (44.104361°, -111.804762°) turn right onto dirt road. Turn left after 6 km at (44.144273°, -111.763308°).
Open: 16-APR to 14-OCT no restrictions.
15-OCT to 15-APR closed for bat hibernation.
Fee: free.
Classification: Speleologylava tube SpeleologyIce cave
Light: none, bring torch
Dimension: T=0 °C
Guided tours:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.



The Civil Defense Caves are large lava tubes. Like most lava tubes in the area they have a low temperature, because of the low average temperature of this area. The collapsed entrances of lava tubes generally form a cold trap, so most caves in the area are SpeleologyIce caves. There is usually ice at the entrance of this cave. Bear this in mind and bring appropriate warm clothes.

Also typical fo lava tubes: there is a tube which is entered through an collapse somewher in the middle. This means, there are always two branches, the two ends of the passage. The section to the south, across the parking area, is bigger and easier to visit. The other branch to the north is narrower and requires some crawling. One part is called Fat Man's Misery, which should gibe an impression.

This caves are open for the public, except during winter when the caves of the whole area are closed for bat hibernation. The caves are not developed, in a somewhat semi wild state, which means there is a road to the cave, a sort of trail or footpath through the cave, but no other developments. Bring good lamps, warm clothes, strudy walking shoes, never go alone, tell someone where you have gone. Follow the general caving saftey rules. On the other hand the cave seems to be rather easy to visit with general hiking ability.

The cave is signposted with wooden posts, at least it was a few years ago. To get there it is necessary to follow a dirt road for about 8 km. After rain the road will be muddy, but under normal condition it is described to be suitable for normal cars. However, it seems the sign got somehow removed, so we decided to add an description, which should make it possible to find the cave with gps.