Gifford Pinchot National Forest
At 2.5 miles long, Ape Cave is the third longest lava tube in North America. Explore a chilly, pitch-black corridor deep beneath the forest floor of Mount St. Helens National Volcanic Monument. A short, paved trail leads to the entrance of the cave, where visitors must descend a series of staircases for self-exploration of the cavern. The 3/4 mile long Lower Cave is relatively easy and family-friendly; most visitors explore the Lower Cave in about an hour. For the more adventurous, the 1.5 mile Upper Cave involves scrambles over rock piles, scaling an 8 foot rock wall, and exiting a small opening in the ground surface before hiking 1.5 miles back to the entrance. The Upper Cave can take 2 hours or more to explore. Visitors must come prepared to explore the cave independently—there are no lights in the cave, so visitors must bring their own headlamps or flashlights. Cell phone lights are not adequate for the cave. More information on the cave can be found here .
To provide for public safety and to protect the delicate cave ecosystem and natural resources, tickets for Ape Cave are required for each vehicle parking on-site. Thank you for your cooperation!
This location uses a timed ticket reservation system to reduce crowding and protect natural resources.
Ape Cave is located on Forest Road 8303, approximately 9 miles east of Cougar, WA, within Mount St. Helens National Volcanic Monument.
Tickets are required, 1 per vehicle, from 9 AM to 5 PM. YOU MUST ARRIVE AT THE BEGINNING OF YOUR RESERVATION TIME WINDOW. Ape Cave is closed to the public outside of these hours. Each ticket is valid for 2 hours of exploration in either the Lower or Upper Cave (within your reserved time window). Reservation holder must be present at arrival. Reservation ID number and time must be clearly displayed in your vehicle. This can be your printed ticket or on a sticky note or piece of paper. If you are unable to make your reserved time, please cancel your ticket by midnight the day before; this will allow others the opportunity to visit Ape Cave.
Visitors can purchase 1 ticket for 1 vehicle per day and a maximum of 6 per year. This ticket must be presented either at the entry booth, Ape Headquarters or the cave entrance.
A Northwest Forest Pass or America the Beautiful Pass is required to park at Ape Cave. If you do not have a pass, you may purchase a Day Pass onsite for $5. Cash or check is preferred. Annual passes are available at Ape Headquarters during hours of operation.
Vault toilet restrooms at Ape Cave will be open, but running water is not available. Please come prepared with hand sanitizer. Drinking water is not available.
Ape Headquarters offers a small selection of snacks, books and gifts, as well as limited flashlight rentals.
Ape Headquarters offers a small selection of snacks. The nearby town of Cougar, WA offers several restaurants and convenience stores.
Ape Cave is just one of many features of Mount St. Helens National Volcanic Monument. For more information on visiting the Monument and Gifford Pinchot National Forest, visit www.fs.usda.gov/main/giffordpinchot .
For organized school field trips and scout outings please use MSHNVM.org to register your group.
Primary Booking Window: Tickets for the 2024 season will be on sale at 7 AM Pacific Time on April 15. Ape Cave will open May 18, 2024.
If you are unable to make your reserved time, please cancel your ticket by midnight the day before. This will allow others the opportunity to visit Ape Cave.
42218 NE Yale Bridge Rd Amboy WA 98601
(360) 449-7800