Craters of the Moon National Monument

Craters of the Moon National Monument and Preserve is a United States National Monument in the Snake River Plain of Central Idaho. The park was created to protect a vast landscape of lava flows with scattered islands of cinder cones and sagebrush. Starting 15,000 years ago, the landscape was created by molten lava flows. While the park's landscape varies tremendously from the celestial body after which it was named, it was nevertheless visited in 1969 by Apollo 14 astronauts Alan Shepard, Edgar Mitchell, Joe Engle and Eugene Cernan who explored the lava landscape in order to learn the basics of volcanic geology in preparation for future trips to the moon.


Lava flows


The park was created in 1924 by President Calvin Coolidge, who at the time described it as "a weird and scenic landscape peculiar to itself". The area was designated the Craters of the Moon Wilderness in 1970 by Congress, the first such designation within the National Park Service.


Over the past 15,000 years, lava eruptions created a rugged but scenic landscape that has forced animals and plants to adapt, and people to endure, detour, or ponder. Located on the Snake River Plain, a volcanic terrain spanning southern Idaho, the Monument and Preserve encompasses the Great Rift volcanic rift zone. In places, this plain is 60 miles wide, with basalt lava deposits over 10,000 feet deep in some locations. Eruptions 2,000 years ago at the Craters of the Moon and the Wapi lava fields are among the most recent volcanic activity to take place anywhere in this immense geographic area. Features visible today include an isolated landscape filled with such features as cinder cones, spatter cones, lava tubes, and several types of lava flows.

Flora and fauna

Flora and lava

Despite the seemingly barren landscape the park supports a rich diversity of life including more than 660 types of plants and over 280 animal species. While searing lava flows that initially destroyed everything in their path today protect the last refuges of intact sagebrush steppe communities on the Snake River Plain. These islands of vegetation, known as kipukas, provide important examples of what is "natural".

Animals seen most frequently in the park are birds and some rodents. The changing weather and seasons play a large role in determining which animals are active at any given time. Most desert animals are nocturnal, or mainly active at night, and include woodrats (also called packrats), skunks, foxes, bobcats, mountain lions, bats, nighthawks, owls, and most other small desert rodents. Animals that are most active at dawn and dusk, when temperatures are cooler than mid-day, are called crepuscular. The subdued morning and evening light helps make them less visible to predators, but is bright enough to allow them to locate food. Crepuscular animals in the park include mule deer, coyotes, porcupines, mountain cottontails, jackrabbits, and many songbirds. The park's diurnal animals are those that are most active during the day, and include ground squirrels, marmots, chipmunks, lizards, snakes, hawks, and eagles. Animals that are unique to Craters of the Moon and the surrounding area include subspecies of Great Basin pocket mouse, pika, yellow pine chipmunk, and yellow-bellied marmot are found nowhere else in the world. Lava tube beetles and many other cave animals are found only in the lava tubes of eastern Idaho.

To date there have been over 212 species of birds sighted on or over the monument and preserve. Many of these are rocky area or shrubland specialists seen in large numbers in only a few other places in the country. Most are found in the areas of the park where water occurs; many small ponds and lakes formed by spring rains and snow melt provide temporary homes for a surprising number of waterbirds, such as ducks, geese, shorebirds, herons, and gulls. Even swans are sighted regularly during the spring migration north to Canada. A few small riparian areas and aspen clumps provide shelter for warblers, vireos, catbirds, orioles, woodpeckers, and more. Small marshes on the northern edge of the lava flow attract blackbirds, wrens, and herons. The park's shrublands supports birds such as Brewer's Sparrows, Sage Sparrows, Sage Thrasher, and Sage Grouse. Limber pine, rocky mountain, and Utah juniper stands growing in cinder gardens and kipuka areas offer habitat to woodpeckers, flycatchers, chickadees, nuthatches, warblers, sparrows, and finches. These patches of trees in the midst of a vast sea of shrublands and barren lava flows are a beacon to many migrating birds, such as warblers, sparrows, and flycatchers, which reside here for brief periods in the spring and fall. The seemingly barren lava flows provide shelter for Mountain Bluebirds, Violet-green Swallows, and Rock Wrens. During the long, cold winters that are characterized by blowing snow and temperatures well below freezing, birds are still found at Craters of the Moon. Ravens, nutcrackers, and chickadees live here all year. Mountain and arctic birds that stay for the winter include Black and Gray Crowned Rosy-finches, Rough-legged Hawks, Northern Shrikes, Snow Buntings, and in some years even Snowy Owls or Gyrfalcons.


 Climate Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily highs (°F) 29 33 42 54 64 74 84 83 72 58 40 28
Nightly lows (°F) 11 14 22 30 38 45 54 52 42 32 21 11
Precipitation (in) 1.7 1.5 1.4 1.3 1.6 1.4 0.7 0.7 0.7 1.1 1.4 2.1

   Data from NOAA (1981-2010)

Extremes of weather and climate prevail at Craters of the Moon across seasons and elevations. From the foothills of the Pioneer Mountains on the northern end of the monument to the Snake River on the south, weather conditions vary significantly. As elevation decreases from north to south, temperatures increase and precipitation decreases. Average annual precipitation ranges from 16 inches at the monument Visitor Center to just under 10 inches near the Snake River at Minidoka Dam. In February, average snow depth ranges from 26 inches at the north end of the monument to just 2 inches at the south end. Intense summer sun bakes the black lava, generating surface temperatures of 170 degrees Fahrenheit and air temperatures in the 90s. Drying winds are a daily occurrence, especially in the afternoon, and may reach 15 to 30 miles per hour. In June, July, and August, the average monthly precipitation is less than two inches. Winter transforms Craters of the Moon into a dramatic landscape of rugged black lava and soft white snow. Fall and spring are milder, with unsettled weather. Despite harsh conditions, delicate wildflowers burst to life in May or June against the more monochromatic background of the cinder slopes: pink monkeyflowers, yellow dwarf buckwheats, white bitterroots, and many others. No matter what the season or the weather, the wide open desert sky at Craters of the Moon offers unobstructed views of spectacular cloud formations, sunrises, sunsets, moonscapes, and stars.

Get in

By car

From Arco, it is about 20 miles (32 km) southwest on US 20/26/93 to the entrance to the monument, about a 30-minute drive. From Carey, it is about 25 miles (40 km) north on US 20/26/93 to the entrance to the monument, about a 35-minute drive.

By air

The closest commercial airport is Idaho Falls Regional Airport (IDA) is just northwest of Idaho Falls. It has limited service from Salt Lake City and Minneapolis/Saint Paul on Delta Connection, Denver on United Express, Las Vegas on Allegiant Air, and Boise and Bozeman on Horizon Air. IDA is located 87 miles (140 km) east of the monument, about a 2-hour drive.

The nearest major airport is Boise Airport (IATA: BOI), 3201 Airport Way, is serviced by several airlines, including United, Delta, Alaska/Horizon and Southwest. BOI is located 178 miles (286 km) west of the monument, about a 3 ½ hour drive.


Park entrance fees are $8 for private vehicles and $4 for individuals on foot, bike and motorcycle. Individuals 15 and under may enter the park for free. All entrance fees are valid for seven days.

There are several passes that allow free entry for groups traveling together in a private vehicle or individuals on foot or on bike. These passes are valid at all national parks including Craters of the Moon National Monument:

In 2016 the National Park Service will offer several days on which entry is free for all national parks: January 18 (Martin Luther King Jr. Day), April 16-24 (National Park Week), August 25-28 (National Park Service's 100th birthday weekend), September 24 (National Public Lands Day), and November 11 (Veterans Day).

Get around

The Monument and Preserve remains open all year, although winter snows prevent automobile access around the Loop Drive from mid-November through mid-April. During the open period the road remains open at all hours.

The paved, 7-mile Loop Road connects all of the park's major attractions. Most visitors drive from parking lot to parking lot, but the road is relatively flat and ideal for bicycling. All major sites include short- to medium-length trails, two of which are wheelchair-accessible.



The 7-mile (11 km) long Loop Road passed many of the key locations in the monument, providing access to trailheads leading to a closer look at the landscape. Listed below are some of the stops along the road.



The only food in the Monument is from vending machines at the Visitors Center. The town of Arco, 30 minutes to the east, is the closest settlement with restaurants and a grocery store.


The only drinks in the Monument are from vending machines at the Visitors Center.



There is no lodging in the monument. The nearest lodging is in the town of Arco 18 miles outside of the park.



Free permits for backcountry camping are available from the visitor center. Although there are no fixed campsites, most of the few backcountry campers at Craters of the Moon hike in to the Echo Crater area on the Wilderness Trail (leaving from the Tree Molds parking lot). The volcanic crater is large enough to accommodate several tents with reasonable privacy, and is close to several cinder cones, volcanic craters, and tree molds.

Be aware: water is not available in the backcountry and, on sunny days, the black cinder ground will heat up quickly. Due to the hot, dry climate, hikers may consume water more quickly than expected--bring at least 1 gallon of water per person per day. Some sources suggest 1.5 gallons. Savvy hikers may wish to do most of their travel before noon, especially if carrying heavy packs.

Stay safe

Cave exploration

The lava tube caves of the Monument are fascinating places to explore but can be dangerous. Take the following precautions when exploring the caves.


The park's black volcanic cinders and rock heat up quickly on sunny days, leading to ground temperatures over 100 degrees. Bring lots of water, and drink it regularly; potable water is not available away from the visitor center and campground.

Go next

Routes through Craters of the Moon National Monument

Boise Mountain Home  W  E  Arco Idaho Falls
Boise Mountain Home  W  E  Arco Idaho Falls
Twin Falls Shoshone  S  N  Arco Salmon

This article is issued from Wikivoyage - version of the Tuesday, October 13, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.