Idaho's Mammoth Cave

100 Mammoth Cave Civil Defense Rd
Shoshone, ID 83352


Millions of years ago there was a violent volcanic eruption north of Shoshone, Idaho. Rivers of molten lava flowed out of the depth of the earth filling a valley 600 feet deep with lava. One of the rivers got blocked off at the head and the molten lava flowed on leaving a hollow tube.

Idaho's Mammoth Cave came into existence. Thousands of years went by. Vegetation grew back. Strange animals lived in the area; camels, little horses, mammoths, strange cats and bears.

A section of the cave collapsed leaving an opening. Bears began using the cave. Stone age man began to use the cave for shelter and a place to preserve their meat in the cool temperature.

The bones of many different bears were found on the floor of the cave. Many broken bones of buffalo, camels, and little horses were found also.

In 1902 some early settlers stumbled onto the cave opening. They didn't have flashlights so they used torches.

They left their names on a wall of the cave with the charcoal from their torches.

In 1954, Richard Olsen, a senior in high school, and his girl friend Veneda, were hunting bobcats in the area. They came onto the entrance of the cave. Richard hiked the 11/2 miles to his car on the highway and got a flashlight.

They headed down into the cave. When they couldn't see the light from the entrance any more, Veneda got scared and started crying. They explored the whole cave with Richard holding her hand, with her crying all the way in and out. Richard had to see what was around each bend. Richard expected to find a great treasure at any time.

Richard got title to the cave under the Small Tract Act and raised mushrooms in the cave for several years. The cave was so majestic and beautiful. He opened it for the entire world to see.

Richard and his wife Linda have had people from every country on the earth come to see the cave.

In the sixties, during the Cold War, the government approached Richard and asked for the use of the cave for a civil defense shelter for people to come to get out of radiation if the United States was attacked.

The Mountain Home Air Base was a target because of the big B52's loaded with hydrogen bombs that it always had ready to fly if we were attacked. They said they would gravel a good road to the cave if Richard would let them put food and supplies in the cave for 8000 people. They built a large platform and supplied food there for the next 20 years

Idaho's Mammoth Cave is not an ice cave, but probably was one for hundreds of years before the vegetation covered the black rock. It maintains a temperature of 41 degrees during both the winter and summer months. It is, at this time, the largest volcanic cave in the world open to the public. Hence the name Idaho's Mammoth Cave, because it is so large.

Several caves in the world have a life form that grows on the walls giving it the appearance of pure silver. Idaho's Mammoth Cave is one of these rare caves. How the life form got here will always be a mystery. It is beautiful to see. Many mineral deposits with their many colors add much beauty to the huge cavern.

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