USGS/CVO Logo, click to link to National USGS Website
USGS/Cascades Volcano Observatory, Vancouver, Washington

Mount St. Helens and Vicinity -
Points of Interest

Ape Cave Lava Tube and Trail of Two Forests

Image, Ape Cave Lava Tube

Ape Cave Lantern Walk -- Join a forest interpreter who will shed some light on the life and features of the cool, dark world of this 1,900-year-old lava tube. Wear warm clothes and sturdy shoes. Lanterns will be provided.
Photo courtesy U.S. Forest Service, Gifford Pinchot National Forest



Driving Directions
  • From Interstate 5 -- take Exit 21 (Woodland Exit)
  • Travel east on Highway 503 and USFS Road 90, approximately 35.7 miles to junction of USFS Roads 83 and 90.
  • Turn north (left) onto USFS Road 83 and proceed another 2 miles to the junction of USFS Roads 83 and 8303.
  • Turn west (left) onto USFS Road 8303 and proceed 0.2 miles to Trail of Two Forests.
  • From Trail of Two Forests - proceed another mile on USFS Road 8303 to parking lot of lower entrance to Ape Cave.


Ape Cave Lava Tube and the Trail of Two Forests

Ape Cave Lava Tube

Explore the furthest reaches of a lava tube formed from an eruption of Mount St. Helens 1,900 years ago. Explore Ape Cave, a lava tube formed when the surface of a lava flow cooled and hardened, but the molten lava beneath the surface continued to flow. The cave opening can be entered with natural light, but for extended exploration, bring three sources of light, sturdy shoes and warm clothing, as the cave averages 42 degrees Fahrenheit. Lantern rentals, travel directions, and Forest Interpreter talks are available daily during the summer season. Ape's Headquarters is located by Ape Cave on Forest Road 8303. Ape Cave was named by members of an outdoor group called the Mount St. Helens Apes. This cave is the longest continuous lava tube in the continental United States. Two different routes of exploration exist inside the cave and an above-ground trail (Ape Cave #239) connects the main and upper entrances. The lower cave is a relatively easy 0.75 mile hike that takes 1 hour round trip. The challenging upper cave is 1.5 miles long, requires climbing over large piles of rocks and takes 2.5 to 3 hours.

Trail Difficulty: Easy to Most Difficult

-- Excerpts from: U. S. Forest Service, Volcano Review: A Visitor's Guide to Mount St. Helens National Volcanic Monument: Summer/Fall 1995, 1997, and 2000; and Doukas, 1990, Road Guide to Volcanic Deposits of Mount St. Helens and Vicinity, Washington: USGS Bulletin 1859

Trail of Two Forests

This 0.25 mile accessible boardwalk trail allows you to venture through a land of lava. Discover the molds or impressions of an ancient forest engulfed by a lava flow nearly 2,000 years ago, and an emerald forest that has risen from the black basaltic lava. If you bring a flashlight along, there is one opportunity to crawl throught the mold of a tree that stood at this site 2,000 years ago.

-- Exceprts from: U. S. Forest Service, Volcano Review: A Visitor's Guide to Mount St. Helens National Volcanic Monument: Summer/Fall 2000



Other Nearby Points of Interest

Map, Mount St. Helens Points of Interest - Interactive Imagemap, click to enlarge Mount St. Helens
Points of Interest -
Interactive Imagemap

Click button for Climbers Bivouac Climber's Bivouac (north)
Click button for Lahar Viewpoint Lahar Viewpoint (east)
Click button for Swift Reservoir Swift Reservoir (south)


Other Menus of Interest


Useful Links

Click button to link to the USFS National Monument Website Link to: USFS Mount St. Helens Attractions - South   [08/04]

ButtonBar
URL for CVO HomePage is: <http://vulcan.wr.usgs.gov/home.html>
URL for this page is: <http://vulcan.wr.usgs.gov/Volcanoes/MSH/NatMonument/PointsInterest/ape_cave.html>
If you have questions or comments please contact: <GS-CVO-WEB@usgs.gov>
08/30/04, Lyn Topinka