Craters of the Moon National Monument

Craters of the Moon is a unique National Monument that explores the lava flows and cinder cones located in south central Idaho. The monument was created in 1924 by Calvin Coolidge to “preserve the unusual and weird volcanic formations”. Nicely put Mr. President, although I prefer “otherworldly” to “weird”. Located on site are a small but informative visitor center, a 7 mile loop drive and a number of hiking trails, and several lava tube caves to explore. Most people will spend less than a day here, but if you want to hike all the trails plan for 2 days. If you wanted to backpack in the wilderness, you could be here a week. Cave entry requires a permit which is obtained at the visitor center. It is difficult to find literature specific to Craters of the Moon, but there is a booklet from the National Park Service that provides an overview. We stayed at the Arco KOA, about 18 miles from the monument. There is a small primitive campground in Craters of the Moon which does not take reservations and claims to be able to accommodate large RV’s and trailers in a limited number of sites.

A lava flow path

Wilderness Trail to Echo Crater

This is the longest trail in the park, about 8 miles round trip with 270 feet of elevation gain. It begins from the Broken Loop Trail, which is located off the Tree Molds drive. As you’re hopping over volcanic rock following the sign posts, spend 15 minutes checking out Buffalo Cave, a small lava tube cave worth your time. Back on the main trail, after 0.6 miles from the parking lot, the wilderness trail takes off to the right, while the Broken Loop Trail continues to the left. Follow the well worn path through sagebrush and over volcanic rock, splitting Big Cinder Butte and Half Cone. After another mile you’ll notice Crescent Butte to the east, while the trail turns towards the west. Another few miles later is the destination, a long extinct volcano now named Echo Crater. To explore the inside of the crater it’s easiest to approach from the north-east; any other approach requires serious down climbing on loose soil with steep drop offs.

View from the rim of Echo Crater

Another view of the rim on the lower side

View of the Wilderness Trail through a more vegetated section

We highly recommend hiking this trail, but do not underestimate the blistering heat present in the summer months. The entire 8 mile trail is on black volcanic soil, which absorbs the sun’s rays and then radiates them back, amplifying the ambient temperature. Combined with few trees for shade and no water sources, unprepared hikers could get into trouble. My recommendation is to hike early in the day, before the sun starts baking the rock. If you’re staying in the nearby town of Arco (as we were), this may mean waking up at 6:00 am. You’ll thank me around 10 am.

The majority of the Wilderness Trail surface is across black cinders

Mike on the Wilderness Trail near Echo Crater

Another view along the Wilderness Trail

Dwarf buckwheat plant grow in cinder areas throughout the monument

Dwarf buckwheat litter the cinders

Stop and check out the side trail to “Lava Trees”, which show lava that flowed and hardened around trees. Years later, once the tree has disintegrated, its form remains

A rift in the lava

Mike at the entrance of Buffalo Cave, located along the Wilderness Trail

Roof in Buffalo Cave

Looking at the entrance of Buffalo Cave from inside

Small Interpretive Hikes

There are a number of small hikes off the Loop Drive, all of which are worth exploring. The first up, soon after entering the park, is North Crater Flow Trail, a well paved 0.25 mile loop trail that introduces the types of lava in the park. Next up is Devils Orchard Nature Trail, a paved 0.5 mile loop that explores various cinder cone fragments that appear like trees in an orchard.

Lava along the North Crater Flow Trail. Haze in background due to forest fire smoke in region.

An example of Blue Dragon Flow, the youngest flow (about 2,100 years ago) in the monument, which has this blue color which comes from a thin outer layer of lava that contains titanium magnetite crystals. Early visitors claimed this marvel resembled the scales of a dragon’s back, hence the name

Along the Devils Orchard trail we saw this tree which developed “witch’s broom”, a dense mass of shoots growing from a single point, with the resulting structure resembling a broom or a bird’s nest due to parasitic dwarf mistletoe

Lava along Devils Orchard is red where the outer blue lava has been broken and removed. This red coloration occurs because basaltic lava rock is high in iron. Metals such as iron rust when they are in contact with oxygen. Oxygen can be found in the air, steam or water, and in the volcanic gases trapped within the cooling lava rock. The gases and water vapor trapped beneath the glassy congealed crust of the lava makes an ideal environment for oxidation to occur, turning the material beneath the crust a red color

An example of Pahoehoe lava which has smooth undulating or ropy masses

We greatly enjoyed the short but steep hike up Inferno Cone, the next stop on the drive. From the top you’ll have the best overview of the entire area. Also on the loop drive are very short trails to Snow Cone and Spatter Cones.

The trail up Inferno Cone is short but steep

Bitterbrush and views from the top of Inferno Cone with smoke haze from regional forest fires

A lone tree on the top of Inferno Cone

People walking up Inferno Cone as viewed from Snow/Spatter Cones

Snow Cone still had last season’s snow at the bottom in early September

Cave Area

Karla at the exit of Indian Cave

There are 4 lava tube caves located about a 0.5 mile hike from the parking lot over a well paved trail. The first one, Dewdrop Cave is very small and frankly not worth exploring. Indian Cave is the largest and tallest, and the only one you can exit at a different point from where you enter. There are also two “skylights” in the this cave, meaning you don’t need a light source. Boyscout Cave is the tightest cave to explore, and the darkest — a light source is required. It’s notable for having ice on parts of the floor year round. Beauty Cave is tall and easy to negotiate, but not very notable.