Idaho National Parks: Spectacular Vistas, Ancient Fossil Beds

City of Rocks National Reserve

The City of Rocks National Reserve is located in the Albion Mountains of southeastern Idaho, near the border with Utah and the town of Almo. The park features a basin and range landscape of gently rolling sagebrush interrupted by a large number of spectacular pinnacles, colorful granite boulders, decorated spires, and delicate-appearing arches. This landscape was created by ancient geological forces, underground lava intrusions from long-dead volcanic activity into some of the oldest rocks in the world. The fascinating patterns seen today on the surface of the City of Rocks were made possible by the processes of tectonic uplift followed by weathering, mass wasting, and erosion.

The geology of the region contains some of the oldest exposed rock formations in the western U.S., known as the Green Creek Complex, an Archean igneous material of coarse-grained, iron-containing granitic rock which was formed 2.5 billion years ago. Overlying the Green Creek is a layer of the Elba Quartzite (Neo-Proterozoic Eon, laid down between 2.5 billion to 542 million years ago), and intruding into both layers are the volcanic materials of the Almo Pluton (Oligocene era, 29 million years ago). 

Visitors exploring the reserve can also enjoy the different plant and animal habitats, such as pinyon-juniper woodlands, aspen-riparian communities, sagebrush steppe, mountain mahogany woodlands, and high elevation meadows. There are over 450 recorded plant species within the park, and 142 bird species, as well as mammals such as mule deer, mountain cottontail, blacktail jackrabbit, yellow-bellied marmots, and reptiles like snakes and lizards.

Craters of The Moon National Monument and Preserve

The Craters of the Moon National Monument and Preserve is situated in the eastern floodplain of the Snake River in central southeastern Idaho. It is a vast region that contains evidence of at least 60 ancient lava flows, and 35 extinct cinder cones covered with sagebrush. The most recent eruptions occurred between 15,000 and 2,000 years ago, creating a lava field covering 618 square miles; but the region is still stretching, with ongoing subtle changes and less subtle earthquakes. The most recent earthquake occurred in 1983, and it measured a magnitude of 6.9.

Native Americans were living here at the time of the last major eruption, 2,000 years ago. Residents of the Shoshone tribe were visited by Lewis and Clark in 1805; and in 1969, the region served as a test laboratory for U.S. Apollo program astronauts Alan Shepherd, Edgar Mitchell, Eugene Cernan, and Joe Engle. At Craters of the Moon and several other national parks, the men explored the lava landscape and learned the basics of volcanic geology in preparation for future trips to the moon. 

The monument also contains large areas of sagebrush steppe, as well as numerous kipukas. Kipukas are isolated islands of remnant vegetation protected by surrounding lava flows that act as small, virtually undisturbed havens for native plants and animals. Hundreds of small kipukas are scattered throughout the Craters of the Moon lava fields.

Lava tube caves, fissure caves, and caves created by differential weathering can be found in the park boundaries. Would-be cavers will have to be screened for white-nose syndrome first, since the caves are inhabited by bats susceptible to the disease. Over 200 species of birds have been sighted on or over the monument and preserve, including Brewer’s sparrows, mountain bluebirds, Clark's nutcracker, and the greater sage grouse.

Hagerman Fossil Beds National Monument

Hagerman Fossil Beds National Monument in the Snake Valley west of Craters of the Moon is nationally and internationally significant for its world-class paleontological resources. The park features one of the world's richest fossil deposits from the late Pliocene epoch, in terms of quality, quantity, and diversity. 

The fossils represent the last vestiges of species that existed before the last Ice Age and the earliest "modern" flora and fauna. The best represented of these is the one-toed Hagerman horse also known as the American zebra, Equus simplicidens. Over 200 of them inhabited the area some 3.5 million years ago, when this valley was a floodplain flowing into ancient Lake Idaho. The horses recovered here were of both sexes and all ages, including many complete skeletons as well as skulls, jaws, and detached bones.

The remarkable set of fossils at Hagerman spans at least 500,000 years and is contained within a continuous, undisturbed stratigraphic record. The fossils deposited represent an entire paleontological ecosystem with a variety of habitats such as wetland, riparian, and grassland savanna.

Although there is no place in the park to see fossils in the ground, the park's visitor center has a cast of a complete Hagerman's horse, as well as special displays and exhibits on the Pliocene fossils. 

Minidoka National Historic Site

The Minidoka National Historic Site, located in the Snake River valley near Jerome, Idaho, preserves the memory of the period during World War II when Japanese internment camps were operated on United States lands.

On December 6, 1941, the Japanese army attacked Pearl Harbor in the Hawaiian islands, propelling the United States into World War II, and intensifying existing hostility towards Japanese-Americans. As wartime hysteria mounted, President Franklin Delano Roosevelt signed Executive Order 9066 forcing over 120,000 people of Japanese ancestry, men, women and children, to leave their homes, jobs, and lives behind and move to one of ten prison camps scattered across the nation. They were given less than a month to leave: Any Japanese remaining within 100 miles of the Pacific coast after March 29, 1942, would be arrested.  

Minidoka opened on August 10, 1942, and at its peak it held 9,397 Japanese and Japanese-Americans from Washington, Oregon, and Alaska. Minidoka contained 500 hastily-constructed wooden buildings, making up a community of 35 blocks of barracks, 3.5 miles long and 1 mile wide. Each block held 250 people, including 12 buildings of six one-room apartments, and shared recreation hall, bathhouse-laundry room, and dining hall. In November 1942, a barbed wire fence was erected around the perimeter of the city and eight watch towers were raised; at one point the fence was even electrified. 

For the next three years, people coped they best they could: farming, educating their children, enlisting or being drafted into the army—over 800 people from the camp served in World War II. On October 28, 1945, the camps were forcibly closed and the people left to reconstruct their lives. Very few returned to the west coast.

The tar-papered barracks, the guard towers, and most of the barbed wire fence have been torn down. What remains is a temporary visitor contact station, a reconstructed guard house, a still-active farm, and a 1.6-mile-long marked trail with posted signs identifying the remains of the historic structures and buildings and telling the story of Minidoka.

Nez Perce National Historic Park

Nez Perce National Historic Park consists of numerous associated sites scattered through four western states: Idaho, Montana, Oregon, and Washington. In Idaho, the sites are primarily located around the Nez Perce Reservation near the Washington state border in west-central Idaho.

The sites are dedicated to several aspects of history and prehistory of the region. The oldest areas are archaeological sites dated between 11,000 and 600 years ago. Most are marked only by a historical marker, but the Buffalo Eddy site contains two groups of rock outcroppings with several petroglyphs—pecked and painted Native American art—on both sides of the Snake River. One side is in Washington and one side is in Idaho, and you can visit both, approximately 20 miles south of Lewiston, Idaho. 

There are several sites which are sacred to the Nez Perce and are associated with interesting tales about Coyote, a trickster god common to many ancient Native American tales. Each has a historical marker telling the stories, but they are all on private property and not accessible to the public. Sites on Mission and Treaty Eras in Idaho are also mostly marked with historical signs but otherwise on private property.

A couple of sites dedicated to the history of American explorers Lewis and Clark's passage through Idaho on their way west to the Pacific and then back east again have some places to explore. At Weippe Prairie, there is a discovery center where you can learn about Lewis and Clark; at Canoe Camp there is a sign-posted hiking trail near the Dworshak Dam and Reservoir. The Lolo Trail and Pass site has a visitor center and a series of historic signs along the old trailway which was used by Lewis and Clark in the first decade of the 19th century.