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Craters of the Moon National Monument and Preserve came to our attention while we were on our cross country trek in our RV. We had a National Parks Passport and were aiming to hit as many places as we could on our drive. But really we had no idea what Craters of the Moon was.
So, what is Craters of the Moon National Monument and Preserve? Located in southern Idaho, Craters of the Moon National Monument and Preserve is an incredible volcanic landscape full of cinder cones, lava beds, and many other volcanic structures. It has a range of walks, caves, and hikes you can explore and boasts scenery unlike any other you will find on this earth.
The entrance fee for the Monument is $20 but is included in your National Parks annual pass. If you are visiting in winter when the Loop Road is not open it is free to enter the park but it’ll have to be on foot/snowshoe/skis.
Table of Contents
About Craters of the Moon
Craters of the Moon is a large lava field covering 618 square miles (1,601 square km). It contains post ice-age lava flows as young as 2,000 years and as old as 15,000 years. The preserve is part of the Great Rift volcanic zone.
On the preserve you’ll find over 25 volcanic cones including cinder cones and spatter cones, 60 unique lava flows, not to mention lava tubes, tree molds, and lava beds.
Eruptions at Craters of the Moon Lava Field tend to be about 2,000 years apart and eerily it’s been 2,000 years since the last eruption. The National Park Service assumes the eruption will occur along the central area of the Great Rift since this is the oldest area but it could extend up to the Loop Road.
The preserve gained it’s protective status in 1924. It has been up for review in the past few years as to whether it should retain it’s status as a National Monument and Preserve. Some think it should be upgraded to National Park status and the Idaho Senate has started petitioning Congress for this designation.
Weather at the Moon
You can almost guarantee it will be windy at Craters of the Moon so pack your windbreaker and tie on your hat. In the winter the northern part of the monument gets a decent amount of snow, averaging about 26 inches while the southern portion will only get about 2 inches.
It gets hot in the summer! Especially with the black lava fields soaking up the solar heat, surface temperatures can reach up to 170 deg F with air temps in the 90s. If you are visiting in July and August be prepared with plenty of water and a hat (and make sure you hold on to it!).
Spring and fall will see minder temperatures but the wind is ever-present. We visited in mid-late June and the sun was blazing and the wind was drying. Beau was happy in shorts, tank top and flip flops (he usually is) while I preferred to wear my windbreaker which provided some sun protection.
What to See
Now technically the preserve is open year round but the Loop Drive is closed in winter, specifically from late November to mid April.
The Loop Drive is a 7-mile loop road with 7 different stops along the way. If you don’t have a lot of time you can just drive the road in about half an hour and get a quick peek at the scenes Craters of the Moon has to offer.
The Loop Drive makes for an easy self-guided tour. You can choose to stop at as many points of interest along the way as you like. Along the trails, there are many info boards to help you understand the different geological features you’re looking at.
Stop 1: Visitor Center
Like all National Parks and Monuments, the visitors center is a wealth of information and should always be your first stop. Here you can get your much needed stamp for your national parks passport.
The downside to this visitors center is it is small and there is limited parking. We were able to snag one of the oversized spots though so we could pop in for our stamp, cave permit, and a little info.
They also offer ranger-led walks throughout the summer. These are typically offered from the beginning of June till the beginning of September and occur at various times during the day.
The daily programs include:
- Inferno Cone Hike – This 45 minute tour takes you on a steep 1/2 mile climb of a volcano. Meet with a ranger at the Inferno Cone parking lot (stop 4)
- Patio Talk – A 15 minute talk about the history of Craters of the Moon, topics change daily and occur at the visitors center.
- Cave Walk – Take a guided tour of the Cave Walk trail (Stop 7). The tour will take about 1.5 hours and cover about a mile of ground. Make sure you have your cave permit and good shoes
- Evening Stroll – This short 1/4 mile walk in the evening takes about 30 minutes and starts at the campground amphitheater. You’ll see amazing views of the lava landscapes surrounding the North Crater cinder cone.
- Junior Ranger – This half-hour learn to be a ranger program is fun for kids and parents too. It takes place in the evenings at the campground amphitheater
- Evening Program – This 45 minute program changes daily specializing in astronomy on Friday nights. This is at the campground amphitheater and will end after dark.
If you plan on entering any of the caves (see stop 7) then you’ll need to get your free cave pass. The purpose of the pass is to go over protection for the local bat population against White Nose Syndrome.
White-Nose Syndrome is a deadly bat fungus that can be easily transported on soft or porous items such as shoes, clothes, and bags. If you have been in any caves outside of the national preserve then you need to ensure these items do not enter the cave with you.
According to the National Parks site if you have been in a cave or mine since 2005 then you need to not bring any item that has entered the caves with your before. The permit lists items like cameras, phones, and flashlight but these usually aren’t soft or porous but to be safe check with the ranger at the visitors center.
White-Nose syndrome has killed millions of bats since it was introduced to the US in 2005. The National Parks Service is trying very hard to stop the spread of the fungus and protect bat populations.
Stop 2: North Crater Flow
North crater flow is a short drive from the visitors center past the entrance to the park, where you pay your entrance fee and the campground.
Here at stop 2, you have two options for a walk. One is a short 1/4 mile loop the other is 3.5 mile walk that dumps you out at stop 5.
We opted for the 1/4 mile loop which unfortunately was under construction so we couldn’t do the full loop but we still more or less saw everything.
The north crater flow boasts some interesting different lava formation like rope lava (I might have gone a little photo crazy with it) as well as cinder cone fragments.
These towering monoliths are fragments of a cinder cone and were ripped from their original cone by molten lava flows. These beasts are common throughout the preserve.
Stop 3: Devils Orchard
The next stop on Loop Drive was Devils Orchard Nature Trail. This is an easy 1/2 mile loop trail that is actually considered wheelchair accessible. It’s fully paved and relatively flat. If you are limited on time in the preserve this is a definite must!
The name was given to the spot by a visiting minister who “declared this jumble of rocks, shrubs, and trees to be a garden fit for the devil himself.”
The orchard is chocked full of wrapped and twisted trees. It’s an easy stroll through an orchard of gnarly trees and small foliage splattered with lava boulders spewed from the last eruption thousands of years ago.
The info signs in the Orchard a geared towards thinking about problems an area like Craters of the Moon is facing but are still give great info on the foliage and formations. Like, did you know lichen are very sensitive to air pollution and the lichen at the preserve show signs of pollution damage?
Stop 4: Inferno Cone
Now, stop 4 is a real hike, it’s a 1/2 mile steep walk to the top of the cone. The path itself is a natural cinder trail but don’t worry its nice an firm.
From the top of the cone, you’ll get some magnificent views of the entire preserve. The panoramic view includes the Great Rift, a 52 mile chain of volcanoes, the Snake River Plain and the Pioneer Mountains.
Stop 5: Spatter Cones
At stop 5 you can take a short walk to see the miniature volcanoes known as spatter cones. Spatter cones are formed from lava spewing from a central vent. I accidentally keep calling them “splatter cones” but it might be an apt description.
There is an accessible viewing platform that will give you some awesome sights of the Monument and you also have the option of walking up one of the spatters cones too.
The trail up the spatter cones is a corkscrewing boardwalk to get you to the top and there you can gaze into the lifeless spire. It was a cool view but you’ll need to brace yourself if it’s windy like usual.
If you chose not to take the North Crater Trail back at stop 2 then you can hike back about a 1/2 mile to get a spectacular view of Big Craters. Or you can hike the entire 3.5 mile trail and end up back at stop 2.
Stop 6: Tree Molds and Broken Top Loop
Stop 6 is the gateway to the Craters of the Moon wilderness. We didn’t have time to do any hikes out this way but there are several to choose from
The Tree Molds Trail is a 2 mile trail that takes you by lava charred trees. The Broken Top Loop Trail is a 1.8 mile loop which circles a cinder cone and has many volcanic features.
The Wilderness Trail takes you 4 miles to lava trees and from here many hikers choose to continue their hike beyond. If you a big into being a visitor of nature you can hike and camp in the wilderness of the preserve. You will need to get an overnight camping permit though and beyond a certain point, there is little to no trail.
Stop 7: Caves
Stop 7 is the highlight of Craters of the Moon for most people. This is where you get to really explore. There are 4 lava tubes or caves, you can explore ranging in difficulty and size.
The caves are Dewdrop, Boy Scout, Beauty and Indian Tunnel. The caves start about a half mile down the path which is a bit of a meandering hilly trek. You’ll find at the parking lot mini cave maps to help you navigate, these you can keep for a donation or just return them to the box for the next explorer.
If you plan on exploring the caves bring a flashlight and good closed toed shoes (or you can be like Beau and do everything in flip flops). Just remember these are wild caves and you are exploring them at your own risks. It’s totally worth it but just be mindful of your footing and low ceilings.
We personally only had time to explore Indian Tunnel but each cave has its own unique set of features so it’s worth exploring them all if you have time.
Dewdrop is the first cave on the trail (about a 1/2 mile) and the smallest of the four. Most of the cave is visible from the trail but it’s a neat little cave to wet your appetite.
It’s a small scramble down some rocks to enter the cave and then you will be in a sort of medium-sized opening. There isn’t much further you can explore here aside from checking out the moss covered rocks.
From Dewdrop Cave you continue along the path to find a fork. You can continue straight to Boy Scout Cave and Beauty Cave or hang a right and check out Indian Tunnel.
Boy Scout Cave
Boy Scout Cave is the chilliest of the caves and actually keeps ice year round even when it’s 100 deg F outside! You’ll likely want a sweater to explore Boy Scout Cave since it’s significantly colder below ground. And for sure take a flashlight!
Boy Scout has two low entrances so you’ll need to crawl to go into the cave. If you pick the right, slightly larger entrance, the cave opens up into a decently large room. You’ll need to be careful of your footing since the ground is uneven and ice and water can make is slippy.
Inside the cave, you’ll see different rock formations and dripping water which forms large crystal-like icicles which sparkle like rhinestones when your light hits them, and lava-ice stalactites fondly called “lavacicles”.
If you decide to go left, the smaller entrance leads to a small chamber which at first glance is underwhelming but if you are feeling adventurous there is small crawl space that will lead you to the rear entrance of the cave. Probably not a good pick for those uncomfortable with tight spaces.
Once you’ve had your fill of Boy Scout Cave and are still ready for more adventure, then you can continue down the path to Beauty Cave.
Beauty Cave has a reasonably large opening but you’ll have to scramble down a rocky slope to enter. It’s a largish cave and is about 300 feet long. Unfortunately, due to unstable ceiling conditions, you can’t explore the entire cave system.
The area that you are allowed to explore has a high ceiling and about 20 feet wide so you won’t feel too closed in compared to Boy Scout and Dewdrop. Early in the season, you can find ice in the cave but it does not remain year round.
Beauty cave is covered with moss, lichen, and unknown cave slime. Near the back of the cave you’ll need your flashlight but don’t go past the barrier.
After you clamber back up the rocks and out of Beauty Cave you can head back down the path to the fork, about a 1/3 of a mile. Going straight will take you back to the parking lot but going left will take you to the largest of the caves, Indian Tunnel.
Indian Tunnel is the largest of the caves but is very open and bright. It is more tunnel-like in feel than cave-like hence the name. According to the National Parks brochure, the tube is 30′ high, 50′ wide and 800′ long.
To enter, a stairway has been built to help visitors safely access the tunnel and if you are up for it you can go all the way to the end where there is an exit. The path through the tunnel is covered with large rocks and boulders.
You’ll need to keep an eye on your footing to prevent turning an ankle but Beau managed in flip flops (partly by choice partly due to visiting another cave with his sneakers). There are many openings in the ceiling of the tunnel so flashlights are not required. The rock walls are covered with moss and golden lichen.
To exit the cave you will need to scale a rock collapse and climb out a hole in the top of the tunnel. It sounds harder than it actually was and was well worth the effort.
To get back to the path you follow posts along the lava field on an unimproved trail. Mind your step and try not to stray since there are openings in the rocks around. The path seemed to take longer than expected (it was only 0.15 mile) but it could just be that it was hard to see where the paved path was.
Where to Stay
There are a few campgrounds near Craters of the Moon, one is actually on the preserve itself. We personally found a sweet free spot for the night down the road a ways.
Lava Flow Campground
This basic campground is located on the Preserve and is open from April-November, weather dependent. There are 42 sites available and it’s only done on a first come-first served basis.
It gets pretty busy in the summer but you may luck out and snag a spot. The cost is $15/night during the main season and $8 if the water is turned off. If you happen to be there in November or April you may even get to stay for free.
There are no hookups, showers or dump station and only some sites can fit larger RVs and trailers. Water is available for immediate use only.
The campground is very exposed to the elements since there are few trees at Craters of the Moon. You’ll be subject to wind and sun and there is nothing around for miles.
But you will see some incredible stars! It is designated an International Dark Sky Park meaning there is very little night pollution and the preserve strives to keep it that way.
If you are looking for hook-ups and the certainty of a reservation then ARCO KOA is only a short 25min drive away. As always the KOA is fully kitted out with wifi, tv, a pool, snack bar, dog park, and even bike rentals.
Of course, all the amenities and hookups come at a price but for about $40 a night it’s not a bad option to have A/C in the middle of the summer.
Since we are frugal travelers and were on our cross country trek we headed about 40 min down the highway to find ourselves a free spot for the night courtesy of freecampsites.net.
Our campground was right on Silver Creek but we had to drive VERY slowly down a dusty washboard road. It took a few attempts to find the spot but it was a well maintained site with brand new picnic shelters and fire pits.
If you are big into fishing then Silver Creek is the place to be!
How to Get to the Preserve
Craters of the Moon National Monument and Preserve is located in southern Idaho along highway 26/20/93. It is halfway between the small towns of Arco and Carey.
The address of the visitors center is 1266 Craters Loop Road. If your GPS is trying to take you to the middle of the preserve then try looking for the Lava Flow Campground instead. Either way, just stick to highway 20 and the visitors center will be obvious. Don’t take any unpaved roads!
From Idaho Falls it is about 84 miles. You head west on highway 20 then in Arco continue southwest along highway 26/20 for about 18 miles.
From Twin Fall it is about 90 miles. You head north on highway 93, at Shoshone you head northeast on highway 93/26 then, in Carey head east on highway 26,20,93 for about 24 miles.
From Boise, it is about 170 miles. You’ll take the highway 84 southeast to Mountain Home then go east on highway 20. In Carey, you’ll continue east on highway 26,20,93 for about 24 miles.