Highlighted by the Mount St. Helens National Volcanic Monument, Gifford Pinchot National Forest is known for its unusual landscape, which includes [tunnels and caverns formed in eons-old cooling lava][9]. The 2.5-mile-long [Ape Cave is an especially popular tourist attraction][10], and a section of the Pacific Crest Trail makes the forest [a popular destination for hikers][11].

Gifford Pinchot National Forest's many rivers, lakes and streams contain a variety of fish like chinook salmon, coho salmon, steelhead trout, cutthroat trout and rainbow trout. Terrestrial species include elk, black bear, mountain goats, and bobcats.

source: https://wilderness.org/11-america%E2%80%99s-greatest-national-forests

[9]: http://www.fs.usda.gov/detail/mountsthelens/about-forest/?cid=STELPRDB5142976
[10]: http://www.ohranger.com/gifford-pinchot-natl-forest
[11]: http://www.fs.usda.gov/attmain/giffordpinchot/specialplaces