Ape Cave Interpretive Site

Explore a chilly, pitch-black lava tube over two miles long. A short, paved, accessible trail beneath towering trees leads to a stairwell into the cave. The ¾ mile, one-way lower cave route is relatively easy and family friendly. For the more adventurous, the 1.5 mile upper cave route leads to a climb up an eight-foot rock wall and scramble over rock piles, then an exit and a 1.5 mile above ground hike back to the parking lot. 

Ape Cave is the third longest lava tube (2.5 miles long) in North America and cave temperature is 42 degrees F/5.6 degrees C year-round. Make sure to bring two sources of light per person (a cell phone light is not bright enough), sturdy shoes, warm clothing, even in warm weather. In summer, Ape Headquarters, a small information station, offers lantern rentals, information and sales items to ticket holders.

Help protect Ape Cave. Please do not touch cave walls or ceiling. Touching kills cave slime, a basis for the food chain of tiny creatures that live there. Help protect our bats and caves from White Nose Syndrome. Practice Leave No Trace principles by packing out all that you bring with you.

Open Seasonally: During the winter from November 1 to May 17, the area is closed to the public, and there is no access allowed without prior authorization, as per 36 CFR 261.53 (b). Access to Ape Cave and Ape Cave Trail #239 is only possible during the open season from May 18 to October 31. 

Reservation System: Timed reservations are required to visit Ape Cave during the open season: May 18 through October 31. Choose a two-hour time slot for your desired day on recreation.gov. 

Frequently Asked Questions: English, Spanish, Russian.

VIDEO - Accessible Adventures: Mt. St. Helens South Side Attractions  (Ape Cave description at 1:58)