
Planning to visit Mount St Helens National Volcanic Monument in Washington State then you must add a visit to Ape Caves Lava tube. It’s one of our favorite adventures in Pacific North West and is a must stop every time we visit Mt St Helens. Ape Caves are adventurous, child friendly and little spooky with the lights shut off.



Have you heard of Ape Caves?
Ape Caves are one of the geological wonders at Mount St. Helens. Ape Caves is a lava tube that is third longest tube in North America that is 13,042 feet long (about 2.4 miles) underground.

Why is it called Ape Caves?
There are no apes in it incase if you were concerned. It is a cave, more like tunnel that is dark, wet and cold. The caves were discovered by a logger named Lawrence Johnson. But the caves were explored in 1950 by members of a Spelunker group known as the Mount St. Helens Apes.
Ape was a word referring to the mysterious legendary creature commonly known as Sasquatch or the Big foot. A hairy creature like a human being reported to exist in the northwestern U.S. and western Canada. Ape Caves thus got its name.

How were Ape Caves formed?
Caves were formed about 2,000 years ago when lava poured down the southern flank of Mount St. Helens in streams. The outer edges of the lava stream cooled forming a hardened crust which insulated the molten lava beneath.

Family Visit to Ape Caves
I love exploring new places with my family. It can be challenging to find interesting family travel destinations that are easy enough to visit with kids and old grand parents. Ape Caves visit is exciting and adventurous for all specially children as they love exploring the dark caves with lanterns or flashlights. My kid was happy to try out his new head lamps.
Exploring the Ape Caves National Volcanic Monument
There is a great trail system around the caves that will lead you through old lava flows. Entrance to the Ape Caves is at short distance from the parking lot. On Entering the large cave entrance, there are two staircases to the floor of cave. There is a signed board at junction between two Caves; referred to as the Lower Cave and the Upper Cave.

Lower Cave
The Lower Cave is an easy walk, for a 1.5-mile round trip and can be hiked down and back in an hour. It is a broad lava tube that gets narrow at some part and then again widens up. The floor is flat, bit uneven and rocky at some portion and then sandy later.

The Lower cave houses a popular geologic anomaly known as the Meatball, a block of cooled lava which fell from the lava tube ceiling while lava was still flowing through the cave. Floating on the surface of the lava flow it was carried downstream until it became wedged in a narrow spot above the present cave floor.
The Lower Cave is exciting and adventurous trip for school age kids that also helps them learn about the lava, volcanoes and the historic volcanic eruption at Mount St. Helens.


Railroad Tracks
As the name indicates, the railroad tracks are a rock formation that runs along the side of the lava tube. It resembles to a railway track. The formation was created when lava drained from the tunnel and left behind minerals on the wall

Tiny chamber
A tiny chamber marks the end of the Lower Cave. It’s only large enough to crouch in and has a very sandy floor. We saw few people crawling through tiny tunnel on their stomach. The tunnel is wide enough for one person. We didn’t try to go further in that tiny chamber as airflow was very poor and there was smell of ammonia that was making me uncomfortable.

There is not much to see at tiny chamber which is the dead end of the Lower Cave but it depends on how much you can explore with your sharp eyes. Kids can crawl in easily if they are not feeling scare and are excited to explore. We did observe something wonderful when my kid was throwing flash right over the end of the dead caves.
The rocks did shine with purple color. For moment we thought may it is purple quartz but not sure it could be though. There were many places in the tunnels which were glittering as gold dust over them when flash light over it. Possibility could not be ruled out that there can be enormous trace minerals in the Caves.

Upper Cave
Upper Cave is 1.5 miles one way and is difficult one that requires more time, caution and good fitness level. This unique hike in ancient lava tubes takes to lava boulders, sharp piles of cutting rocks and uneven rocky floor. Some portion requires climbing up over and around abrasive rocks, walking over lower ceiling above you.


At times we need to be careful not to hit head on sharp ceiling. Also, one needs to take care not to twist an ankle in some places. We turned back from this hiking in Upper Cave as it was taking good enough time and our flash light battery got over. Upper Cave hike is one of the most unusual hikes that are available in Gifford Pinchot National Forest.
Things to Remember for the Ape Caves
Lanterns, Head lamps and Flashlights
The most important thing, there is no light source in the lava tube. Visitors need to bring their own lights or lanterns. It is dangerous to explore the cave without proper light as there are many obstacles like boulder piles, low ceilings, and sharp rocks.
We were wearing Head Lamps along with Lanterns and Flash Lights in hand. I recommend having two to three strong light sources per person for maximum safety. Remember your phone’s flashlight doesn’t count.

In case you don’t have Lanterns, you can rent them at the Ape Headquarters in summer. Lanterns are one of the best light sources available because the volcanic walls don’t adsorb their light well. The Ape Caves are open year-round but be sure to check snow conditions in winter before making the drive.
Sturdy Water Proof Footwear
There are large, boulder rocks at some portion in Lower Cave and most of the Upper Cave. The ceilings are drippy, and there may be puddles. So Good Water proof footwear is must to navigate in the Caves.
If you’re planning to explore the Upper Cave, plan only if you are physically fit to navigate large rocks piles in boulder part with little light. Also take care not to hit your head to sharp lava ceiling and not twist or turn your ankle.
- No pets are allowed in the cave.
- Bring a Light Jacket or Raincoat. It gets cold down there, and there are some lava stalactites that drip water.
- Do not take any rocks from the caves. It’s not allowed.
- No food or beverages allowed inside the cave.
- Do not touch the walls. Touching the wall could contaminate or damage the cave life.
- To Park and visit the caves, Visitor needs “America the Beautiful” or “Northwest Forest Pass”. However, you can buy a day pass once you arrive from March- November.

Ape Caves Bats
When you are at the Ape Caves National Volcanic Monument, you get to see this yellow sign boards about Ape Caves Bats. It is interesting to learn about this and how it affects the life of Bats. White-nose syndrome is a disease caused by a fungus that grows on nose of affected bats.
It is considered one of the worst wildlife diseases in modern times having killed millions of bats across North America. Affected bats wake up and fly around when they should be hibernating, using up vital fat reserves needed for winter survival. We didn’t see any bats during our visit in Caves.


Where is Ape Caves National Volcanic Monument
It takes around 3.5 hours drive from Seattle to Ape Caves, Cougar depending on traffic conditions. Follow I-5 S to Dike Access Rd in Cowlitz County. Take exit 22 from I-5 S. Take Lewis River Rd to Ape Caves.
Other Places to Visit at Mount St. Helens Washington
Johnston Ridge Observatory offers closest view of Mount St. Helens and the destruction site of volcanic eruption that can be explored on north side. There are many other recreational activities that can be done. Do read on Mount St. Helens National Volcanic Monument.

Where to Stay in Cougar?
Couple Stay/Mid Range Resort – Lone Fir Resort . This is only place that is nearest to Ape Caves, Climbers Bivouac trail head and Marble Mountain Snow Park. This Resort is famous among Climbers and Hikers who are climbing the Mount St. Helens with Permits. It gets fully booked due to its proximity and limited number of Rooms. They have options for Cabins, Tent sites and RV ground.
Have you visited any Caves that are engulfed in darkness and cold? What do you think of visiting Ape Caves at Cougar, Washington?
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Omg what an amazing experience! I had no idea what Ape Caves were! This is so interesting! I’m too chicken for this!
Wow! I live in Seattle and I didn’t realize that this was so close. Thanks for sharing such an in-depth post. I think i’ll definitely have to add Ape Caves to my bucket list now.
I once visited a mineral crystal cave a long time ago when I was much younger! So I’d definitely love to go experience it again now that I’m older! I’m sure it’s just breathtaking!
-Madi xo
Wow, this is a great activity to teach kids about lava/caves/etc. I’ll definitely remember this for any future trips to the Mount St. Helens area.
This looks amazing. I didn’t even know something like this existed. Must plan a trip.
I am inspired! We haven’t been to Washington yet, but we’ve been planning a trip out west and I think we’re going to add Mt St Helens to our itenerary.
I have chills just about thinking of visiting dark/humid/closed places like this. I wish I had the courage! Meanwhile, I’m happy with your pics and how great you described it, such a nice experience!
What an exciting adventure trip! I have already been visiting caves and it’s an special experience getting down the ground
Thank you for this post! I was just at Mount St. Helens tw o weeks ago to show my inlaws, and my husabdn and I plan to go back to hike and maybe camp for a night nearby – I’m definitely adding this cave trail to our itinerary!
– Sarah
You find the most interesting places! Love the photos—hopefully I’ll be able to visit Washington state in the next few years.
I honestly thought the cave had apes in them. 😁. Was like, I’d rather just go to the zoo😏. Thankfully there are none. Nice info. Thanks for sharing.
wow i love the photos! thanks for sharing this post! this looks like a great experience!
This looks like so much fun! Definitely adding this to the list of places to visit as a family!
So cool! I hope to visit one day! I’m so glad you posted—I did not even know about this!
This is definitely a perfect place if you are up for an adventure! Great photos!
Thanks for showing us around the Caves. I’m from Australia – it’s been a while since I’ve visited the USA – but you’ve given me another place to add to my list.
Wow what a cool adventure, it reminds a bit of the lava tubes in Hawaii which are pretty cool if you get a chance to tour them.
My kids love caves, and they would definitely love this! It’s quite a distance away, but you never know where we’ll decide to go in the future!
O wow I would love to visit here! Everything is so beautiful and it’s looks like such an awesome adventure. I’m glad you shared this because I learned something new!
When my son was younger, he was fascinated with caves and we explored so many in Pennsylvania, West Virginia, and Tennessee. However, we’ve never explored a lava cave. When we finally get to Washington state, we’re definitely visiting Mt. St. Helens and checking this one out.
This looks awesome! My family loves this sort of thing 🙂 I’ll definitely have to add it to my list for the next time I’m in the area.
Eeeek, not sure I want to run into any bats but wow kids and adults alike would find this fascinating. Definitely a spot we should visit!
I’ve never explored a cave before, this looks really fun!
very nice place must see
I’ve never heard about Ape Caves or lava tubes before. What an amazing place to visit! I loved cave exploring as a child, so I would definitely put it on my list while visiting National Volcanic Monument.
I had never heard of these caves before, such a funny story of how they got their name. I usually don’t really like caves, they are all so similar and dark. However, this one sounds pretty with the glittering walls and purple hue.
I’m from Vancouver and visit Washington lots. Not gonna lie, I was definitely misled by the name and thought this was a cave full of apes hahaa. Interesting to know how it got its name and wow, its history really does go way back! Never knew this place existed until now and will definitely have to check it out the next time I’m back.
We’ve taken several road trips through Washington State but somehow never had the chance to visiting St. Helens National Volcanic Monument till now. I am really intrigued by the Apes Cave now though after reading your informative post and would love to head there with my family. Interesting to read about how the Ape Caves got that name and how the railroad tracks were created when the lava flow receded. Thanks for sharing the details.
Coming from Seattle, I’m surprised I’ve never heard of the Ape Caves! It looks like such a fun adventure and I love that you write about how to be prepared; I could totally see people venturing down there with only a phone flashlight and thinking that’s enough! Thanks for sharing; I’ll mark this as something to see the next time I’m back home in Washington State 🙂
In 1991 my son fell through the trail of going to the ape caves and fell 30 feet. He survived but was in a coma for 9 days and lost his spleen thank you Dorenbecher Children’s hospital for bring my son back to me. God bless the EMTs who were home from Iraq and came to his rescue being first on site. They saw him fall and quickly went to him to help.