s/y Nine of Cups
Craters of the Moon National Monument, Idaho
May 2012
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Located in the Snake River Plain in central Idaho, Craters of the Moon National Monument and
Preserve was the next stop on our itinerary. The protected area's features are volcanic and represent
one of the best preserved flood basalt areas in the continental United States. Established as a
Monument  in 1924, it was expanded in November 2000. The Monument encompasses three major
lava fields and about 400 mi² of sagebrush steppe grasslands. All three lava fields lie along the Great Rift
of Idaho, with some of the best examples of open rift cracks in the world, including the deepest known
on Earth at 800 feet (240 m). There are excellent examples of almost every variety of basaltic lava as
well as tree molds (cavities left by lava-incinerated trees) and lava tubes (a type of cave).
Upon entering the monument area, the
terrain changed suddenly from
productive farmlands to barren,
grey-black lava rock as far as the eye
could see. We headed to the Visitor's
Center first, got our permit for visiting
the caves and a map of the Loop Road.
The 60 distinct lava flows that
form the Craters of the Moon
Lava Field range in age from
15,000 to just 2,000 years.
Craters of the Moon National
Monument was proclaimed on
May 2, 1924 by U.S. President
Calvin Coolidge to "preserve the
unusual and weird volcanic
Apollo astronaut,
Alan Shepard,
performed part of his
training at Craters of
the Moon Lava
Field,  learning to
look for and collect
good rock specimens
in an unfamiliar and
harsh environment.
A short trail crosses one of the youngest flows to monoliths, crater fragments rafted here by
lava flows. Island-like lava fragments stand in a sea of cinders in the Devil's Orchard. Limber
pines are deformed as the result of the parasite, dwarf mistletoe, and are called "witches'
broom". The tangled, gnarled trees add to the eerie look and feel of the area.
Despite the harsh environment, flowers still grow. Fleabane to the left and mountain
strawberry (right) eke out a life between the cracks and rifts in the basalt.
Lava tubes are natural conduits through which lava
travels beneath the surface of a lava flow, expelled
by a volcano during an eruption. They can be
actively draining lava from a source, or can be
extinct, meaning the lava flow has ceased and the
rock has cooled and left a long, cave-like channel.

We were very interested in exploring some of the
lava tubes at Craters, hence the reason for
obtaining the cave permit. We had lava-tubed in
the Galapagos Islands, but never explored any in
the US. These tubes were shorter and less
intimidating, but interesting nonetheless.
Natural light entered the cave via
holes in the crust.
Some of the tubes, like the Dewdrop Cave
above, have collapsed over time.
A close-up of the interior of  Indian Tunnel
shows drips of lava on the cave's ceiling
that cooled and solidified before dropping.
White-nose syndrome, a disease which
affects the caves' bats is a real concern and
we had to disinfect our shoes before
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We didn't see any bats, but rock pigeons and violet-green swallows continually
swooped through the cave providing an eerie "swoosh" above our heads as we
negotiated the sharp, rugged terrain along the length of the cave.
Climbing out of Indian Tunnel through a tiny hole in the cave's ceiling was a bit of a scramble. We followed a well-marked  trail
across the lava field back to the pathway.
A native American proverb...
The bright blue sky, snow-capped mountains in
the distance and sparse green vegetation
provided a sharp contrast to the barren, black
lava fields.
Next national park on our list?
Yellowstone, the world's first national park and
it's spectacular. Are you coming?
Have you checked out:
National Parks & Monuments?

American Odyssey...Part I?
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American Odyssey...Part II?
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American Odyssey...Part III?
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