The Longest Lava Tube In The Country Is Right Here In Washington, And You Can Walk Through It
Washington is full of breathtaking natural wonders, and that includes some impressive remnants of our prehistoric past. The notorious Ape Cave is more than just a fun hike — it’s also the longest lava tube in the continental United States. If you’re looking for a great trail the whole family can experience, look no further.

To reach it, take Exit 21 from I-5 and State Route 503, then go straight on Spur 50, which will become Forest Road 90. Turn left on FR 83, drive for 1.7 miles, then turn left on FR 8303. You'll see signs for the parking lot.

You can walk through the caves in any season, but they're specially pleasant in the spring and summer.
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The caves themselves are just over 2 miles long.
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The upper section is a bit more challenging. The lower cave is easier and shorter at 0.8 miles.

It requires stepping over some sharp boulders and climbing an 8-foot wall. The lower section is a lot shorter and more spacious.

No pets are allowed, you're not allowed to smoke or bring food, and you should try not to touch the walls and disrupt the cave slime, a food source in the cave’s delicate ecosystem.

Bring extra flashlights and headlamps so you don't lose visibility.
Have you explored the Ape Caves? They’re definitely one of Washington’s most incredible attractions.
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