Cave Regulations

National Park Service
U.S. Department of the Interior

Superintendent's Compendium
Of Designations, Closures, Permit
Requirements and Other Restrictions
Imposed Under Discretionary Authority.

James A. Morris, Superintendent

Craters of the Moon
National Monument
18 m SW of Arco, Hwy 93
P.O. Box 29
Arco, ID 83213

208-527-3257 phone
208-527-3073 fax

CRMO Superintendent's Compendium

Determination based upon 36 CFR 1.5 (a)(1), 1.5(c) Closures and Public Use Limits and 1.6 (a) Permits

Entry into closed sections of caves is prohibited.

Entry into Surprise Cave is prohibited unless authorized by permit issued by the Superintendent.

History of closures: The process began when the park geologist, Doug Owen, perceived there were ceiling instabilities in some of the high visitation caves that could potentially put visitors at significant risk. He requested that Mining Engineer Phil Cloues, NPS Geologic Resources Division, examine the high visitation caves for hazards because of his specialized training and experience in rock properties and mechanics. Phil did so on May 17 & 18 of 2000 and noted several ceiling stability concerns, and as a result temporary closures were made immediately. During the temporary closures, Joel Despain, a cave specialist with Sequoia & Kings Canyon National Parks and Scott and April Earl of the Idaho Cave Survey also examined the caves. The park used the information and recommendations of all these subject matter specialists to make the management decisions and actions described below and completed in 2001.

Beauty Cave- the backroom of Beauty is closed at the start of the crawlway at the back of the front room and at the backdoor entrance with barriers and signs. The ceiling in the backroom is very unstable and a ceiling failure has the potential to propagate all the way to the surface forming a new skylight. Closure will remain in effect until such time as frost wedging or other natural processes cause ceiling failure.

Surprise Cave- the entrance to Surprise is extremely unstable and collapse could seal the cave shut, potentially trapping people not caught in the initial rock fall inside the cave. Cave is closed at entrance with barriers and signs.

Buffalo Caves- the backdoor to Buffalo is closed with barriers and signs, the rest remains open. The ceiling of the backdoor area is very thin and in a process of failing as evidenced by the floor debris. Light can be seen through failed portions of the ceiling. Closure will remain in effect until nature takes its course.

Boy Scout Cave- a ceiling block in the south room, which is not well anchored in the front, but appears fairly well constrained in the back has been cordoned off and signed to keep people from passing beneath it. Loose rock at the entranceway to the north room has been removed. All of Boy Scout, which was temporarily closed, has been reopened with the exception of the cordoned off area.

map of closed area

map of closed area


Last updated: February 28, 2015

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Mailing Address:

Craters of the Moon National Monument and Preserve
P.O. Box 29

Arco, ID 83213


(208) 527-1300

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