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Explore the Ape Caves

Cougar, Washington

based on 9 reviews


Added by Mitch Pittman

Walking around in lava tubes. The darkest dark you've ever experienced. Many other adventures nearby. Options for many skill levels. Explore in any season.

As if erupting volcanoes weren't awesome enough, ancient lava flows also left behind these giant, hollow tubes as they cooled. Spend all day exploring deep underground in this 2.5 mile cave.

To get there, head to the SOUTH side of Mount Saint Helens. You must pass through the town of Cougar to get here, DON'T go to the Johnston Ridge Observatory.

Now, let's explore some caves! It's a short walk from the parking lot to the main cave entrance. Take time to read about how the caves were formed, how they were discovered, and why they're called the 'Ape' Caves. I won't ruin it for you, but it's all interesting!

Descend into the lava tubes first down a stone staircase then a metal one. Make sure you have multiple light sources with fresh batteries. It is extremely dark down there and you don't want to run out of light down there.

The cave is divided into the upper and lower portions. The lower is easier, shorter, and must be done as an out-and-back. Follow the tube as it wiggles deeper into the ground, and pass features such as 'The Meatball' and the 'Railroad Tracks.'

The upper cave is more difficult to negotiate, with large rock piles to scramble over and an 8' lava wall to deal with. There is also a skylight and another entrance/exit at the top of the cave, with a path back to the main cave entrance.

This is an exciting adventure that can be paired with others in the southern Mount Saint Helens area, such as the Lava Canyon, Ape Canyon, or a hike up the south side of the mountain.

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Easy Parking
Family Friendly

Explore the Ape Caves Reviews

Me and my wife knowing that the ape caves were closed due to winter season decided to check out the area again just to see the snow and the landscape in the winter. Let me tell you we were not disappointed it was absolutely stunning walked down a couple trails that weren’t closed and enjoyed the scenery that this beautiful state has to offer will definitely head back to the caves when they open again but a trip up in the winter is worth the drive.

Did this one on a high school field trip! So so fun!! Highly recommend

I never knew you could hike through lava tubs, until now. This hike will take you underground into old lava tubes. Be sure to bring a headlamp, lantern, flashlight, etc and bring extra batteries for all of them. We opted to do this hike backwards and I only recommend it if you're athletic and are comfortable crawling DOWN very steep slippery places. If you hike the tube uphill, it would probably be easier to climb up some of the places inside than climb down them. I don't recommend this hike for anyone who is scared of the dark or claustrophobic.

The Ape Caves are such a perfect example of lava tubes in the Cascades, and they're pretty family-friendly to explore. We stuck to the shorter of the two having just climbed St. Helens, but it would be neat to take the longer cave and pop out the far exit in the forest somewhere.

Did the easier of the two and had a good time. It's a fun place to do some long exposure photography with your lights. Definitely bring a jacket and good lighting you can depend on.

This was a wonderful cave experience to say the least. It's super dark which is amazing for those of us that love that adrenaline rush. The easy lower section was a nice walk, but if you want a real hike I definitely suggest tackling the upper section too. There's quite a bit of scrambling throughout! Major downside is that there's quite a bit of trash in both sections and human feces in the upper, along with some graffiti which takes some of the fun out of it.

Leave No Trace

Always practice Leave No Trace ethics on your adventures and follow local regulations. Please explore responsibly!


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