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Underground tunnel through old lava tubes.

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Point to Point

2,458' 749 m


2,081' 634 m


369' 112 m


377' 115 m



Avg Grade (3°)


Max Grade (8°)

Dogs No Dogs

Features Cave

As of October 2021, a $2 timed entry parking ticket is required. recreation.gov/timed-entry/…


Looking for a different type of journey? This trail that includes navigating an underground tunnel through old lava tubes is sure to please! Just make sure to bring the headlamp!

Need to Know

You'll NEED a strong flashlight, headlamp, or lantern. The ranger station at the trailhead will rent a lantern for a nominal fee. The USFS recommends at least two light sources and extra batteries. You'll also need warm layers. The tunnel stays 42 degrees year round as it is insulated from the weather outside.

Note that while leashed dogs are allowed on the surface trails around the cave, they are NOT permitted inside the cave itself. It is not safe for them (the floor of the cave can be sharp and may cut paws) or considerate for other cave users. Dogs may also be carriers of white-nose syndrome, a fungus-borne disease that can be fatal to bats.


A short distance from the parking lot brings you to the entrance to the tunnel. The tunnel itself is straight-forward, and there is no way to get lost, although there are two sections. The lower tunnel is fairly easy, with no obstacles. It is very good for children.

The upper tunnel requires some light scrambling: As you navigate the upper tunnel, expect to climb over rocks that have fallen into the pathway. Once you reach the end of the upper tunnel, you'll see a ladder leading back to the surface.

Following the path will take you back to the parking lot through a forested trail. The darkness of the cave, in contrast to the vitality of the forest excites the senses, and will make any visitor appreciate the various flora and fauna along the path.


Shared By:

Ben Wagner with improvements by Cameron Booth and 1 other

Trail Ratings

  4.6 from 28 votes


  4.6 from 28 votes
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in Washington


4 Views Last Month
2,311 Since Dec 17, 2015
Intermediate/Difficult Intermediate/Difficult



Taking off the headlamp at the end of the upper tunnel.
Dec 18, 2015 near Amboy, WA
Fun with colors in the Ape Cave.
Dec 28, 2015 near Amboy, WA
One of the few openings to natural light in Ape Cave.
Dec 16, 2015 near Amboy, WA
Ape Cave Lava Tube: Beneath the famous Meat Ball
Dec 28, 2015 near Amboy, WA
The darkness in the Ape Cave is both unearthly and exciting.
Dec 28, 2015 near Amboy, WA
The Ape Cave (Lava Tube) is the main attraction.
Dec 28, 2015 near Amboy, WA


Current Trail Conditions

All Clear 15 days ago
Add Your Check-In


Sep 12, 2021
Jamie F
Sep 2, 2021
Shannon Tokumaru
With alaina June 2021
Jul 2, 2021
Emily R
Great day to hit the caves! 2.5mi
Sep 7, 2019
Mia Arn
Aug 3, 2019
Connor White
Took the upper cave this time; lots of scrambling and fitting through small gaps made for an exciting time! The trail back was pretty too! 4mi — 1h 30m
Jul 20, 2019
Adriann Jordan
Thigh-burner and ankle breaker! Lol! Upper cave! 4mi
Jun 28, 2019
Lauren LeFebvre
Did lower (easier) cave.
Jun 24, 2019
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