Have you ever seen the movies The Descent or The Cave? That’s precisely what came to mind as we made our way through the pitch-black, wet darkness of the Ape Cave lava tubes at Mount St. Helens. Surrounded by nothing except solidified lava, with rainwater dripping constantly from every angle, being inside the Ape Cave felt like being trapped in a cold, wet, boarded-up basement. If you ever get the chance to be away from others, turn off your flashlight and stand still, all you’ll hear is drip… drip… drip. And all you’ll see is… absolutely nothing.
Formed only about 2,000 years ago after a volcanic eruption, the Ape Cave lava tubes stretch a combined 2.5 miles. They are located within the Mount St. Helens National Volcanic Monument. After the eruption, the outer edges of the lava flow cooled and hardened, forming a crust over the molten interior. Once the inner lava emptied, it left behind a hollow tube. Discovered by loggers around 1950, the cave was named after a Boy Scout troop called the Mount St. Helens Apes, who were among the first to explore it after its discovery.
Located in southwestern Washington, the cave is about 1.5 hours northeast of Portland and the Oregon border. From Seattle, it’s roughly a 3-hour drive south, and from the Mount Rainier area, where we came from, expect around 2.5 hours. The cave is situated within the Gifford Pinchot National Forest, part of the Mount St. Helens National Volcanic Monument, in a fairly remote area; however, the drive itself is manageable. In the fall, the scenery is actually quite beautiful, making the drive pleasant, with colorful leaves falling and fog rolling through the forested mountains.
With a year-round temperature of 42 °F., it’s best to dress warmly. We wore hoodies, jackets, leggings, fluffy socks, and hiking boots. I strongly recommend wearing hiking boots. Even if you don’t own hiking boots, you should definitely avoid wearing sandals of any kind. Since the cave is entirely underground, you can expect total darkness, aside from the occasional blinding light from a fellow hiker’s headlamp or flashlight – which I highly recommend you bring yourself. I do not suggest relying on your phone. Due to the rocky, uneven path and total darkness, it would be easy to drop it on the hard, rocky surface or lose it among the piles of lava rocks.
There are two lava tubes – an upper and a lower – with the upper tube being the more challenging. The lower tube is much easier, almost a leisurely stroll, and stretches about 0.75 miles. A sign near the mouth of the cave recommends allowing 1.5 hours to complete it; however, we finished in about an hour. The path is out-and-back, so you’ll eventually reach a dead end and need to turn around. Although the terrain is uneven and requires careful stepping, it remains relatively flat overall.
The upper tube, on the other hand, is significantly more challenging. There are not one, not two, not three, but SEVEN massive piles of fallen lava rocks that you have to scramble over, entirely in the darkness and wetness. Much of the tube slopes slightly uphill, and there’s even an 8-foot “lava fall” you must climb. The path stretches 1.5 miles straight through, and the sign at the mouth of the cave recommends allowing 2.5 hours to complete it. Once you reach the far end, you must then hike back to the parking lot through the woods. We didn’t get to finish the upper path, as two men coming back out told us it was flooded around the quarter-mile mark.
We made it over 4 of the 7 rock piles and climbed the lava fall before calling it quits. By then, we were sweaty, very wet, and tired, and didn’t want to push on only to have to eventually turn back. We warned everyone who asked why we were turning back about the flooded section.
Importantly – Visiting the lava tubes requires a timed reservation and a ticket, at the surprisingly low price of $2 per car. Tickets can be purchased through the Viator app, and I strongly recommend booking as far in advance as possible. You must select an entry time, with a 30-minute window allowed, and these slots can fill up quickly. We visited in late October, with our entry time between 11 am and 11:30 am, arriving around 10:45 am. At that time, the parking lot was mostly empty, and we didn’t see any other visitors. By the time we left around 1 pm, however, the lot was full, with cars lining the road and crowds of people milling about. Many were entering the cave just as we were leaving. I shudder to think what it must be like during the peak summer season.
This is particularly important because one of the most appealing aspects of the lava tube is its solitude. While it can be very eerie, it’s also fascinating to turn off your flashlight or headlamp and stand in total darkness, seeing and hearing absolutely nothing except the slow drip of water. It’s surreal and otherworldly. When the tubes are crowded, that experience completely disappears. Not only is there light pollution from other hikers’ flashlights and headlamps, but far more disruptive is their voices echoing loudly throughout the tubes. Even if they’re a hundred feet ahead or behind you, if they’re loud, you WILL hear them.
Our experience in the tube was a mixture of fortunate and unfortunate moments. At times, we found ourselves near very loud groups of hikers, suffering from their constant noise pollution. One group in particular kept making ridiculous growling and howling noises. At other times, we were utterly alone, able to turn off our flashlights and experience the lava tubes in their entirety and natural state. So, as can be seen, it’s essential to secure a ticket as early in the day as possible, regardless of the season. Otherwise, be prepared to be surrounded by crowds, bright lights, endless chatter, and the occasional weird cave growler.
Next to the parking lot, you’ll find two sets of park-style porta-potties, some maps, and a small gift shop with very limited souvenirs. The gift shop is also where you can pick up a piece of paper and a pen to write down your reservation number and entry time to display on your car’s dashboard if the entry ticket booth is closed (as it was when we visited). Closer to the mouth of the cave, there’s a small, covered rotunda with informative signs about the cave’s history, formation, and surrounding ecosystems. This is also where you’ll find a shoe-cleaning area, where visitors are expected to swipe their shoes before entering the cave.
An important note: no food, pets, smoking, or rock collecting is allowed inside the cave. It’s also strongly recommended not to touch the walls, as they harbor “cave slime,” which is not only gross to touch but also serves as a vital food source for the cave’s delicate ecosystem. Please follow these guidelines and don’t be inconsiderate, unlike the terrible person who left behind urine-soaked napkins in the upper cave… a truly disgusting sight.
Overall, if you’re ever in the Portland, Seattle, or Mount Rainier areas – or anywhere nearby – and you’re looking for a unique outdoor adventure, I highly recommend a trip to the Ape Cave lava tubes. It’s a rare experience that’s sure to leave a lasting memory, and it doubles as a great workout. While the upper cave is strongly recommended for those without mobility or vision issues, the lower cave is relatively easy to navigate and accessible to most visitors, granted they have the correct footwear and a reliable light source. So come and get your cave-dwelling on!
