Arco, Idaho: Lava Fields, Lava Tubes & Charlie’s Birthday
Craters of the Moon National Monument & Preserve protects one of the largest basaltic lava fields in the continental United States. Thousands of years ago, volcanic eruptions covered the landscape with rivers of lava, creating cinder cones, lava tubes, craters, and rock formations that today feel almost otherworldly.
It has been on our National Park list for a while, and I wasn’t really sure what to expect. Everyone we talked to seemed to love it.
After finally seeing it for ourselves…I think our opinion lands somewhere in the middle.
It’s unlike anywhere we’ve been before. Miles of black lava fields stretch in every direction, making it feel more like another planet than Idaho. It was fascinating to see once, but it wasn’t one of those places that immediately jumped onto our list of favorite family adventures.
One thing the park does exceptionally well is its layout.
Everything is organized along a scenic driving loop with numbered stops, so you can experience the highlights without committing to one long hike. We spent about 3–4 hours there, which felt like the perfect amount of time. It never felt rushed, but it also didn’t take our entire day.
Worth the Detour?
Some places become destinations. Others become stops along the journey.
Arco was definitely the second for us.
We spent the week here almost entirely because of Craters of the Moon National Monument & Preserve. Outside of that, Arco is a small town with limited grocery options and not a whole lot going on. It’s the kind of place you stay because it’s close to what you came to see—not because the town itself is the attraction.
Would we make a special trip back? Probably not.
But we’re still glad we came.
Craters of the Moon
Worth the Detour? ⭐⭐⭐☆☆
Time Needed: 3–4 hours
Best For: Families, geology lovers, photographers, National Park enthusiasts, and anyone working toward visiting every National Park Service site.
Dog Friendly: No. Dogs are not allowed on the park’s hiking trails.
Stroller/Wheelchair Friendly: Only the North Crater Flow boardwalk and visitor center are fully accessible. Most other stops involve uneven lava rock, stairs, or steep terrain.
Bike Friendly: Yes! The scenic loop is approximately 10 miles and is a popular ride for cyclists.
Food: Pack a lunch. There are picnic tables throughout the park, but no food service beyond possible snacks at the visitor center.
Water: Refill your bottles at the visitor center before starting the scenic loop.
Bathrooms: Flush restrooms at the visitor center; vault toilets throughout the rest of the park.
Shade: ⭐☆☆☆☆ Very little to none.
Craters of the Moon
Our first stop was the visitor center.
As always, the kids grabbed their Junior Ranger booklets while we collected another National Park Passport stamp. Before leaving, we picked up our free cave permits. If you go, don’t skip this step. Because of White-nose Syndrome, permits are required before entering the lava tube caves, and those caves ended up being our favorite part of the entire park.
From there we started making our way around the loop.
North Crater Flow was a nice introduction to the landscape. The paved boardwalk makes it the most accessible stop in the park, and it gives you a chance to really appreciate how massive the lava fields are without much walking.
Inferno Cone came next.
Calling it a “short hike” is technically true…
Calling it “easy” would not be.
The climb is steep enough that it had me stopping more than once while Eli and the kids somehow managed to make it look effortless. By the time we reached the top, the wind was absolutely ripping across the summit. It was cold, rainy, and honestly a little miserable—but the panoramic views across the lava fields were incredible. Sometimes those are the moments you end up remembering the most.
After that, the Spatter Cones and Snow Cone were nice, quick stops. They’re easy walks where you can look directly into volcanic cones, and they were a fun change of pace before heading to the caves.
The caves completely stole the show.
Indian Tunnel was our favorite. After climbing down into the lava tube, we wandered through the cave using the flashlights on our phones. They worked, but next time I’d definitely bring headlamps. Having both hands free would have made climbing around much easier.
Dewdrop Cave was where I drew the line, for myself at least
The entrance is much tighter, and being claustrophobic, there was absolutely no chance I was squeezing down there.
Eli, on the other hand, climbed in with the kids without hesitation. They discovered a narrow tunnel that connected to another opening underground and thought it was the coolest thing ever. Hearing them excitedly tell me about it afterward was enough for me—I was perfectly happy staying above ground.
By the time we finished the loop, we had another set of Junior Ranger badges, another National Park site checked off our list, and three tired kids who had spent the day climbing over ancient lava flows.
Not a bad day.
A few practical notes if you’re planning to visit: pack your own lunch, because there really isn’t food available once you’re inside the park. There are picnic tables throughout the loop, very little shade, and the only water refill station is at the visitor center. Flush bathrooms are there as well, while the rest of the park has vault toilets. We also found that the park became busier as the day went on, so arriving early is probably your best bet.
Don’t Skip the Cave Permit
Before you leave the visitor center, get your free cave permit.
Because of White-nose Syndrome—a fungal disease that has devastated bat populations—everyone visiting the caves must watch a short informational briefing before receiving a permit.
Nobody checked our permits during our visit, but we still recommend getting one. It only takes a few minutes, helps protect the bats, and saves you from wondering if you’ll need it later.
The caves ended up being the highlight of our day.
Our Favorite Stops
1. Indian Tunnel & Dewdrop Cave ⭐⭐⭐⭐⭐
Without question, these were our favorite stops in the park.
The walk to the caves is about 1.6 miles round trip over uneven lava rock.
Indian Tunnel is a massive lava tube that you climb down into before walking through underground. There is some rock scrambling, but all three of our kids (ages 12, 9, and 5) handled it without any issues. It’s not stroller or wheelchair accessible.
We used the flashlights on our phones, which worked just fine, but next time we’d definitely bring headlamps so our hands were free.
Dewdrop Cave was a different story.
It’s much tighter and requires climbing straight down into the opening. I skipped this one because I’m claustrophobic, but Eli and the kids loved it. They even found a small tunnel that connected underground to another opening, and crawling through it became one of the kids’ favorite memories from the trip.
If you only have time for one stop, make it the caves.
2. Inferno Cone ⭐⭐⭐⭐☆
This hike is short…but don’t let that fool you.
It’s incredibly steep.
I struggled quite a bit climbing it, while Eli and the kids made it look easy.
We visited during the summer but had cold temperatures, rain, and incredibly strong winds. By the time we reached the summit, the wind was so intense that we didn’t stay very long.
Still, the panoramic 360-degree views across the lava fields were beautiful and absolutely worth the climb.
Bring layers—even in summer.
3. Spatter Cones & Snow Cone ⭐⭐⭐⭐☆
These were fun, quick stops where you can walk right up to volcanic cones and look inside.
The walks are short with very little elevation gain, making them easy additions to the scenic drive.
4. North Crater Flow ⭐⭐⭐⭐☆
This is the park’s most accessible stop and a great introduction to the volcanic landscape.
A fully paved 0.3-mile boardwalk loops through a lava flow that erupted about 2,100 years ago. It’s educational, easy to walk, and gives you a great appreciation for just how unusual this landscape really is.
A Few Things to Know Before You Go
- Plan on spending about 3–4 hours if you want to experience the highlights.
- Arrive earlier in the day if possible. The park became noticeably busier by the afternoon.
- There is very little shade anywhere in the park.
- Pack plenty of water and refill your bottles before leaving the visitor center.
- Pack lunch or snacks. There isn’t food available once you’re driving the loop, although there are picnic tables if you want to stop and eat.
- The weather changes quickly. Even in summer, we experienced cold temperatures, rain, and very strong winds.
- Stop at the visitor center first for your Junior Ranger booklet, National Park Passport stamp, cave permit, and flush bathrooms.
- Bring headlamps if you plan on exploring the lava tubes.
- If you only have time for the highlights, we’d prioritize North Crater Flow, Inferno Cone, the Spatter & Snow Cones, and finish with Indian Tunnel and Dewdrop Cave.
Charlie’s Birthday Adventure
Charlie had one request for her birthday.
She wanted to go shooting.
That probably tells you everything you need to know about our family.
We found a public shooting area outside of town on BLM land. It wasn’t fancy—just homemade targets and a patch of open desert—but honestly that made it even better. We had the place almost entirely to ourselves and spent the afternoon practicing together. It ended up being one of those simple memories that probably won’t make most travel guides but will always make us smile.
A Surprise Favorite: Challis Hot Springs
The biggest surprise of the week wasn’t in Arco at all.
It was Challis Hot Springs.
About an hour and a half away, the drive winds through beautiful Idaho ranchland before arriving at a family-run hot springs connected to an RV park.
Admission was only $10 per person (children under five were free), plus a small parking fee.
The large pool was spotless, naturally heated, and almost too warm for the kids on a hot summer afternoon. They eventually figured out that the coolest spot was right next to the pipe where fresh water flowed into the pool, and that’s where they spent most of their time.
The smaller soaking pool was much hotter and much quieter. It felt like the place you’d want to come back to on a cool evening after a long day of hiking.
One of my favorite details was seeing the actual hot spring bubbling beside the pools. A sign said the water was around 119 degrees, and it reminded me so much of Yellowstone’s thermal areas.
It was affordable, uncrowded, clean, and such a relaxing way to celebrate Charlie’s birthday.
If you’re spending several days around Arco, we’d absolutely recommend making the drive.
So… Was Arco Worth it?
I think so—but with the right expectations.
If you’re driving through southern Idaho or trying to visit every National Park Service site, absolutely make the stop. Craters of the Moon is unlike anywhere else we’ve been, and the lava tube caves alone made the visit worthwhile.
If you’re choosing one destination for an unforgettable family vacation, this probably wouldn’t be our first recommendation.
Still, when I think back on our week, I won’t remember whether every hike was worth five stars.
I’ll remember standing on top of Inferno Cone trying not to get blown away. I’ll remember waiting outside Dewdrop Cave while Eli and the kids disappeared underground. I’ll remember Charlie grinning through her birthday at the shooting range and later floating in the warm water at Challis Hot Springs.
And honestly, those are the memories that matter most.
