"ape cave"

Pictured: Mt. St. Helens from Ape Cave upper exitI do have an appreciation for Pacific Northwest hiking.
Ape Cave, on the south side of Mt. St. Helens National Volcanic Monument (fee area), is the longest known lava tube in North America.
Fred Barstad has a good description of the hike in his guide (ISBN 978-1560446965, Falcon Guide), however I disagree with his difficulty rating. The upper cave is quite doable for experienced hikers (with an adequate light source of course). I do not believe that a person has to be an expert caver. I certainly am not! There is no crawling involved, and it's not very strenuous, but moderate. The 8 foot lava falls is slightly challenging. While lava tubes are not colorful (all black and dark), they are a neat, exciting experience. You are probably getting wet if you misstep in the tube (just ankle high at most). It is of course always damp, like any deep cave.
The upper cave heads uphill for just over a mile, then upon exiting, a person can take a one mile exterior trail back to the trail head.
Vehicle access, when open, is via Woodland, Washington and Rt. 503.
The nearby Trail of Two Forests is short and worthwhile.

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