Southern Idaho is home to two geologic marvels: Craters of the Moon National Monument and Preserve and City of Rocks National Reserve.
Both are a little bit off the beaten path and both highlight the tremendous forces of the earth, but the two are very different from each other in terms of how each highlights the natural beauty of the forces of nature.
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Craters of the Moon
Located near the town of Arco, ID, getting to Craters of the Moon NM from our campground in American Falls was about a two-hour drive through large stretches of the Idaho National Laboratory.
Robert Limbert, a part-time explorer, coined the term “craters of the moon” to describe the massive lava fields located north of Minidoka. In fact, astronauts have trained on the lava fields before heading to the moon itself.
Otherworldly. That’s the term I would use. Craters of the Moon does not feel like any place I have ever been to. Yes, I have been to volcanos and seen lava fields before, but this was unlike any of that.
Let’s talk about lava for a moment. I have never seen so many different types of lava before. We took a four-mile hike out to the lava trees. What struck both Bonnie and I was the variety of lava. One moment, you are walking across fairly smooth lava, the next, craggy, broken pieces surround you in what looks like an impassable field. Then, you find yourself walking through a field of sparse vegetation growing in the cinders… Followed by a low pine forest.
Despite the impression of a desert, you can find life. There are plenty of flowers growing in the cinders, animals can be found mulling around in the sagebrush.
Still, it’s a stark landscape of extremes.
Visiting Craters of the Moon
Craters of the Moon NM can easily be visited in a day without feeling like you have missed much.
The main attraction is the park road, which is not long and has a one-way loop.
There are several short trails which are easy to walk. The first you pass is the Devil’s Orchard, an accessible trail through an “orchard” of large chunks of lava and small trees.
The second “easy” trail you will pass is the trail to the top of Inferno Cone. The trail is short, but it is all uphill. I was a bit winded by the top of the cone, but uphills affect me for whatever reason.
The view from the top of Inferno Cone is so worth the hike. If you do no other hikes in the park, hike the Inferno Cone and the Devil’s Orchard.
Following the loop, you will run into the Snow Cone and Spatter Cones. Both are pretty cool, especially considering we found unmelted snow in the bottom of the Snow Cone.
The North Crater Trail ends there, as well. You can hike up the first 1/4 mile to find a great crater without hiking the 3.5-mile one-way trail.
Hikes and Caves
If you follow the loop road, you will come across a spur that will lead you to the trailheads for a couple of trails. We took the Broken Top Loop to the Wilderness Trail and followed the Wilderness Trail out to the lava trees, which are molds of upright trees in the lava.
On the way back, we completed the Broken Top Loop for a total of four miles on the trail. A note about hiking in Craters of the Moon NM: there is no shade. At all. None. While the temperatures were mild (low- to mid-80s), we still felt cooked by the sun.
The lava fields are also home to several caves, including a lava tube, which is located towards the end of the loop road. There are four caves along a T-trail.
We went in both the Beauty Cave and the Dewdrop Cave. Both caves were difficult to get down into, requiring a scramble down large pieces of broken lava.
The caves were interesting, but not nearly as beautiful as Lehman Caves in Great Basin National Park. What was amazing was how cold they were. There was ice on the floors of the caves and no light at all. Be sure to bring your headlamps!
All of the caves require a permit from the park service due to White-nose syndrome. Check in with rangers at the visitor center to obtain a permit and make sure you bring nothing into the cave you have used in other caves.
Final Thoughts on Craters of the Moon NM
This is one of the more unique places I have ever been to. While there is not a ton to do other than the loop road, it is well worth your visit to see this unique landscape. I would certainly budget a day to explore the monument and do some hiking.
There is a campground that has water and restrooms, but there are no hook-ups, so plan accordingly. The preserve portion of the park covers a much larger area with miles of backcountry trails and roads. Check with the rangers for information on backcountry hiking and the Bureau of Land Management in Shoshone, Idaho for information on the backcountry roads.
City of Rocks National Reserve
City of Rocks NR is interesting, both from a geologic and National Parks perspective. Located between Almo and Oakley, Idaho, it is not far south from I-84.
It is a garden of granite spires nestled in the hills among the sagebrush and pines of southern Idaho. To be honest, it reminds me a lot of the Black Hills of South Dakota, only on a smaller scale.
From a National Parks perspective, City of Rocks NR is a bit unique… it is a National Reserve. There are only three national reserves in the park system. This one is even more unique in that the Idaho Department of Parks and Recreation manages it, along with the nearby Castle Rocks State Park.
The national reserve designation allows for private landowners within the park, as well as hunting and ranching.
City of Rocks is also home to part of the California Trail and has a couple of rocks where emigrants headed west left their names written in axle grease.
City of Rocks is home to some of the best rock climbing in the world and the park is truly geared toward that end. While there are campgrounds within the park and some very pretty views, it became very obvious this park is geared toward climbing.
The hikes we took led us to various climbing spots and, while the trails were ok, it was apparent the quality of the trails was an afterthought to getting climbers to their routes.
Final Thoughts on City of Rocks NR
It’s cool. If you have never been to the Black Hills, the landscape is quite unique. If you aren’t a climber, there’s not a lot to do there, but it is not too far out of your way for a half-day visit, more if you want to try out a few of the trails.
Other Parks Sites in Southern Idaho
I would be bereft if I did not mention the other two National Parks sites in southern Idaho: Minidoka National Historic Site and Hagerman Fossil Beds National Monument.
Both are located a short drive off I-84 between City of Rocks NR and Craters of the Moon NM.
Minidoka NHS is the site of a Japanese internment camp during World War II and Hagerman Fossil Beds NM preserves the site where the fossils of the first horse were found.
We visited those sites back in 2015 on our winter road trip and you can read about them here.