Escape the heat in the third longest lava tube in North America! Ape Cave, located in the Gifford Pinchot National Forest on the south side of Mount St. Helens in Washington, is a 13,042 foot long tunnel that was formed over 2,000 years ago when lava flowed down the mountain in streams, cooling and forming an outer crust. The name comes from the scout troop (their sponsor was the St. Helens Apes) that discovered the cave in the early 1950’s. The sponsor’s name may have come from an old term used for foresters in the area, “brush apes,” or from the legend of Bigfoot. There are two cave routes: lower cave and upper cave. Both routes take you through a pitch-black adventure, with uneven ground and a constant temperature of 42 degrees Fahrenheit. Two light sources per person are recommended, as well as sturdy shoes, gloves, and layers. The lower cave is a family-friendly, 1.5 mile round trip, out and back walk, while the upper cave is a strenuous, 1.5 mile one way trek with multiple rock piles to climb over and an 8 foot lava wall to scale. Keep an eye out for Bigfoot as you explore Ape Cave!