August 2, 2015 Arco, Idaho

IMG_0831It was a long travel day from West Yellowstone to Arco, Idaho with a stop along the way at the Walmart in Idaho Falls to restock supplies.  Arco is a tiny town with a population of 995 and was the first community in the world to be lit by electricity generated by nuclear power.  This occurred on July 17, 1955.  The area is nothing but sagebrush and open fields and the campground selection is very limited so we settled in at a KOA. The local high school paints their graduation year on the rocks above the city.IMG_0829IMG_0832

IMG_0828Our main reason for coming to this desolate area of Idaho was to visit the 750,000 acre Craters of the Moon National Monument and Preserve located eighteen miles southwest of Arco.  In 1924 President Calvin Coolidge used the 1906 Antiquities Act to proclaim the Craters of the Moon National Monument.  In 1923 geologist Harold T. Stearns described the area as “the surface of the moon as seen through a telescope…. where dark craters and the cold lava were nearly destitute of vegetation”.

IMG_0788While lava flows exist on the moon, astronauts confirmed that most lunar craters resulted from meteorite impacts, not from volcanoes.  But the Craters of the Moon are definitely of volcanic origin.  The vast amount of lava did not come from one volcano but from a series of deep fissures, known as the Great Rift, that cross the Snake River Plain.  Beginning 15,000 years ago lava welled up from the Great Rift to produce this vast area of rock.  The most recent eruption occurred 2,000 years ago and geologists believe future eruptions are likely.IMG_0789IMG_0790IMG_0794IMG_0795IMG_0826IMG_0827


Satellite view of the lava flows

Years ago the Northern Shoshone Indians passed through this area on their annual migration from the Snake River to the Camas Prairie.  They left behind well worn trails and mysterious stone circles on top of the lava.  Archeological evidence and oral traditions indicate the Shoshones most likely witnessed some volcanic eruptions.

Craters of the Moon can be seen by satellite and we noticed it shows up on the local TV weather maps when we watch the weather.

In the 1800’s European-Americans in search of gold and farmland avoided the lava fields.  In the 1850s and 1860s pioneers followed the Goodale’s Cutoff of the Oregon Trail as an alternate route to avoid conflicts with the Shoshones and crossed through the northern edge of the lava fields.  Idaho was part of the Oregon Territory then.  In 1863 it became the Idaho Territory and a state in 1890.

In 1969 NASA Apollo astronauts learned about volcanic geology here in preparation for their moon missions.


Splatter cone

After stopping by the Visitors Center we drove the Craters of the Moon Loop Road, stopping at various places along the route.  The final stop had a trail across the lava that led to several lava tubes or caves.  Entering the caves required some tricky rock scrambling so I was happy to leave the cave exploring to Bill.


Indian Tunnel


Indian Tunnel


Indian Tunnel


Indian Tunnel



Boy Scout Cave looking deep


Entrance to Beauty Cave


Beauty Cave

IMG_0833Also while in Arco we drove to see the Experimental Breeder Reactor #1 (known as EBR-1) at the Idaho National Laboratory.  On December 20, 1951 the reactor became the first nuclear reactor to generate a usable amount of electricity using atomic energy.  From that day until the day it was decommissioned in 1964, EBR-1 generated enough electricity to supply all the power for its own building whenever the reactor operated.

We took a guided tour through the building which explained how atomic energy is used to make electricity.  We had an excellent guide, a University of Idaho graduate student in psychology from the Ukraine.  We were surprised she didn’t have a degree in nuclear engineering.  There wasn’t a question asked she couldn’t answer in detail.IMG_0838IMG_0840

President Lyndon Johnson visited the site in 1966 during a ceremony dedicating EBR-1 as a registered National Historic Landmark.

Among many things our guide told us was that the nuclear waste materials from the Three Mile Island accident site was brought to Idaho to be stored.  It was often brought across the country by train in darkness because of protests by people in states who did not want the waste passing through their states, with some states forbidding the passage.


Physicist Enrico Fermi was the genius behind the “breeder” concept, but Walter Zinn made it a reality.

The Idaho National Laboratory currently employs more than 8,000 people.IMG_0843

Who knew this desolate area of Idaho could hold such fascinating places!

One thought on “August 2, 2015 Arco, Idaho

  1. karnold249

    I spent some time getting caught up on your posts, and it was so much fun seeing the places in Yellowstone we visited about 6 years ago, as well as Grand Tetons and Jackson Hole. Enjoyed seeing the before and after picture of Bill on Yellostone Lake. Sorry to hear about shingles but glad it wasn’t a big problem. You going to get the shot after? We are in Iowa tonight and Sioux Falls tomorrow. Onto Colorado by Sunday. Thanks for the great blog….wish it would send me an email when you post something though. Karen

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