The Ape Caves are one of the most fascinating places to explore in Washington. You can find these ancient lava tubes in the Gifford Pinchot National Forest, on the south side of Mount St. Helens. At a little over 2 miles long, they’re known as the longest lava tubes in the lower 48 states. The caves feature an upper and a lower level, both of which offer an invigorating hike through the underground.

Do you like to go spelunking? Have you been to Ape Caves before?

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